Download PDF
Review Article  |  Open Access  |  27 Nov 2024

Textile electronics for ubiquitous health monitoring

Views: 114 |  Downloads: 19 |  Cited:  0
Soft Sci 2024;4:40.
10.20517/ss.2024.37 |  © The Author(s) 2024.
Author Information
Article Notes
Cite This Article

Abstract

The emergence of wearable electronics, along with an increased emphasis on personal health, has catalyzed a transformation in conventional health monitoring methods. Textile electronics are attracting significant attention due to their good flexibility, breathability, biocompatibility, portability and wearability, positioning them as a promising platform for human health monitoring. Consequently, substantial efforts are being dedicated to developing multifunctional, integrated, and reliable health monitoring systems based on textile electronics. This review summarizes recent advancements in textile electronics, focusing on materials, preparation techniques for functional fibers and fabrics, design strategies for textile-based health monitoring systems, and applications in ubiquitous health monitoring. Additionally, some emerging strategies for integration are presented. Moreover, the challenges and future outlook of textile electronics, along with potential solutions are discussed.

Keywords

Textile electronics, functional fiber, healthcare monitoring, integration strategies, wearable electronics

INTRODUCTION

As artificial intelligence (AI) evolves and human demands increase, wearable electronics are emerging as platforms for the next generation of multifunctional and user-friendly intelligent devices[1-4]. Ideal wearable electronics possess properties of excellent wearability and durability[5-8]. Consequently, researchers are striving to develop wearable technologies that exhibit superior electrical performance while ensuring excellent deformability and comfort. Textile electronics, a crucial component of the smart wearable devices sector, integrates textile technologies with electronic engineering principles to facilitate the generation, transmission, assessment, and modulation of electronics on fibrous substrates[9-11]. Characterized by their inherent softness, comfort, breathability, and washability, textile electronics have been extensively integrated into various applications, particularly in human health monitoring[12-15].

Health is fundamental to human survival and development, and health issues present societal concerns and scientific challenges. The advent of textile electronics has ushered in a new era for adaptable health monitoring solutions within consumer electronics markets[16,17]. These advanced devices integrate functional fibers to facilitate the transmission of information between the human body and the surrounding environment, as well as in vivo and in vitro, with exceptional interactive capabilities[18-20]. In contrast to conventional thin-film patch sensors, textile-based health monitoring systems offer superior breathability and enhanced wearability, which are essential for comprehensive large-scale sensing capabilities[18,21,22]. Textile electronics for health monitoring can be realized through two primary pathways. The first approach involves directly affixing electronic components onto the surface of textiles or integrating them as hybrid electronic elements within the textiles[23,24]. Subsequently, flexible or fabric circuits are employed to establish wired connections between microelectronic components and textiles. The alternative approach entails producing fibers with electronic functionalities, which are then woven into textiles[25-28].

Research on textile electronics for health monitoring dates back to the 1960s and 1970s[29], with the introduction of concepts such as shape memory fiber materials and intelligent fiber materials, which laid the groundwork for the field. Most textile electronics were developed by attaching electronic components to textiles using the first approach in the early stage[30]. For example, the Georgia Tech Wearable Motherboard was developed in 1999, and the firefly dress was created by the MIT Media Laboratory around 2000[23,31]. In the early 2000s, the EU-funded project WEALTHY developed a textile sensor system to monitor patients’ physiological signals, such as electrocardiograms (ECG) and breathing, in real time[32-35]. This system represents a significant advancement in the use of textile electronics for medical health monitoring. Subsequently, more textile electrodes for physiological monitoring arose, and textile electronics with wireless personal area networks were progressively utilized in health monitoring[36,37]. In 2012, researchers at Ohio State University developed textile antennas and circuits with a precision of 0.5 mm[24]. Subsequent advancements improved this precision to 0.1 mm, representing a significant milestone in textile electronics[38]. These wearable antennas can transmit and receive digital information, significantly enhancing communication capabilities for health monitoring systems[24,39-41]. With advancements in internet technology, cloud computing platforms have been incorporated into textile-based health systems for efficient processing of health big data. Subsequently, smart platforms based on various functional fibers have been successfully developed for electromyography (EMG) and sleep monitoring[42,43]. These studies demonstrate that textile electronics obtained through the second approach not only maintain the comfort and functionality of traditional clothing but also integrate advanced electronic functions, contributing to the realization of a fully electronic textile system. In recent years, the development of smart textile electronics has entered a flourishing stage[44-48]. Machine learning algorithms and advanced integration technology have greatly advanced the intelligence and integration of health monitoring systems[49-52]. Figure 1 illustrates the above evolution of textile electronics in health monitoring applications. Moving forward, the realization of a fully textile-based health monitoring system will be a primary research direction. It is anticipated that textile electronics will transform human lifestyles through real-time health management and remote medical care, in conjunction with AI, human-computer interaction, and cloud computing technology.

Textile electronics for ubiquitous health monitoring

Figure 1. Timeline of textile electronic developments for health monitoring. Figure “WEALTHY: physiological monitoring”[35], reprinted with permission. Copyright 2011, Elsevier; Figure “TENG for respiratory monitoring”[53], reprinted with permission. Copyright 2016, John Wiley and Sons; Figure “EMG”[43], reprinted with permission. Copyright 2017, John Wiley and Sons; Figure “Sleeping monitoring”[42], reprinted with permission. Copyright 2017, John Wiley and Sons; Figure “Fabric for sweat monitoring”[47], reprinted with permission. Copyright 2018, John Wiley and Sons; Figure “Wound healing”, reprinted with permission. Copyright 2020, Elsevier; Figure “Pulse & respiratory monitoring”[45], reprinted with permission. Copyright 2020, Science Advances; Figure “IC textile”[51], reprinted with permission. Copyright 2021, Springer Nature; Figure “Pregnancy monitoring”[44], reprinted with permission. Copyright 2022, American Chemical Society; Figure “Multifunction”[52], reprinted with permission. Copyright 2023, Elsevier; Figure “Stress management”[49], reprinted with permission. Copyright 2024, John Wiley and Sons. TENG: Triboelectric nanogenerator; EMG: electromyography; IC: integrated circuit.

In this review, we systematically introduce innovative textile electronics and summarize their latest advancements in health monitoring systems. We begin with an overview of the materials utilized in textile electronics, followed by an analysis of the fabrication techniques for functional fibers and fabrics. Next, we discuss various design strategies for developing textile-based health monitoring systems. Furthermore, recent applications of textile electronics in ubiquitous health monitoring are discussed. The latest integration strategies are then presented, representing pivotal advancements toward the commercialization of textile electronics. Finally, we emphasize the critical challenges faced by health monitoring systems based on textile electronics. Our discussion aims to cover advanced materials, fabrication techniques, applications, and integration strategies in this promising field.

MATERIALS OF TEXTILE ELECTRONICS

Functional materials

The performance of textile electronics is significantly influenced by functional materials, which endow textiles with conductive and sensing properties. The selection of materials demands a meticulous assessment of pivotal attributes, such as electrical conductivity, mechanical resilience, thermal stability, specific weight and density, thermal dissipation capacity, and the reliability and longevity essential for integration with conventional wire interconnections[54,55]. These characteristics are fundamental to ensuring the functionality and robustness of textile electronics in various applications. Figure 2 presents an overview of the prevalent functional materials for the preparation of textile electronics, categorized into metals, conductive polymers, carbon materials, and semiconductors[54,56].

Textile electronics for ubiquitous health monitoring

Figure 2. Images of various functional materials for textile electronics.

Metals such as Au, Ag, and Pt are highly valued for their exceptional electrical and thermal conductivity. These metals are available in a spectrum of dimensions, from 0D to 3D structures, as shown in Figure 2A. Among them, Ag nanoparticles have garnered extensive applications due to their remarkable electrical conductivity, stability, and the simplicity of their synthesis process[57,58]. Furthermore, the core-shell structured composite metal nanoparticles offer a viable alternative for the fabrication of textile electronics. Although metal alloying can improve strength and corrosion resistance, it potentially decreases conductivity relative to pure metals, alongside elevated costs and enhanced processing complexity[59,60].

As shown in Figure 2B, conductive polymers involve conventional varieties [such as polyaniline, polypyrrole, polythiophene and poly(ethylene dioxythiophene)][61-65], conductive hydrogels[66-68], and conductive liquids encapsulated by polymers[69]. These materials are notably lightweight and highly flexible, making them suitable candidates for textile electronics and their interconnects[70,71]. Although their conductivity can be adjusted through physical or chemical means, it remains lower than that of metals, necessitating doping for performance enhancement[72].

Carbon materials, such as carbon black, carbon nanotubes (CNTs), graphene, and reduced graphene oxide (rGO), are known for their inherent electrical conductivity, excellent thermal conductivity, and low weight [Figure 2C][73-76]. However, they may present challenges related to dispersibility and compatibility with other materials[77,78]. Moreover, as depicted in Figure 2D, zinc oxide (ZnO)[79,80], organic/inorganic perovskites[81,82], and transition metal dichalcogenides (TMDs)[83,84] have shown considerable potential for applications in sensing and display modules of health monitoring systems.

Mechanical polymers

In textile electronics, mechanically flexible/stretchable polymers play an important role, especially as flexible substrates, conductive fibers and encapsulation layers. The three-dimensional network structure of polymeric matrixes can be used to carry, support and protect other materials, such as the previously mentioned functional materials. In textile electronics, mechanical polymers should be selected based on requirements for flexibility, stretchability, biocompatibility, and compatibility with functional materials.

For fabricating flexible substrates, there are some examples provided for consideration, such as using polyimide (PI) as a substrate directly[85], coating polyvinyl chloride (PVC)/polyurethane (PU) on textiles to be suitable for lithographic processes[86], and using polyethylene terephthalate (PET) fiber as a substrate for coaxial configuration[87,88]. Besides, the polymers are employed for fabricating conductive fibers, such as Au nanowires@styrene-ethylene/butylene-styrene (SEBS)[89], Ag nanoparticles@poly(styrene-block-butadienstyrene) (SBS)[90], GO@PU[91], etc. Moreover, the polymers are employed for encapsulation layers such as ecoffex[92], polydimethylsiloxane (PDMS)[93], PI[94], etc.

In addition to the functional materials and mechanical polymers, other materials are also employed to enrich the functionality of textile electronics. For instance, pharmaceuticals are being embedded into fibers to enable long-term therapeutic applications[95]. Furthermore, efforts are underway to integrate antibacterial materials into textiles to suppress or eliminate bacteria and provide additional protection for users[96], especially in scenarios where strict hygiene standards are crucial.

FABRICATION TECHNIQUES

Textiles are complex hierarchical materials requiring specialized knowledge of manufacturing processes. As the fundamental units of textiles, fibers can be processed into yarns through twisting or texturing[97,98]. These yarns can be crafted into fabrics using various techniques, including weaving, knitting, or bonding[99]. Given the importance of electrical performance in textile electronics, it is crucial to innovate and enhance the fabrication techniques of textile electronics according to the framework of traditional textile production processes. This section introduces fabrication techniques for functional fibers and fabrics, highlighting their significance in developing textile electronics.

Fabrication of functional fibers

Surface treatment for commercial fibers

Conductive fibers are typically obtained through wire drawing, which involves elongating metal wires into fiber forms. Metals such as stainless steel, copper, and aluminum are commonly used in this method. Fibers with diameters ranging from a few to tens of microns can be fabricated by drawing the metal wires through a series of precision dies[100,101]. However, most commercial fibers are primarily insulators[102-106], so their conductivity can be achieved by applying conductive materials via dip-coating[90,107]. Lee et al. employed this technique for the fabrication of conductive fibers[90]. In their method, theSBS polymer was immersed in a silver-containing solution (AgCF3 COO). This immersion allowed for the infiltration of Ag into the SBS, enhancing electrical conductivity of SBS. Thereafter, the silver nanowire (Ag NW)-coated fiber was coated using the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) solution. This approach was demonstrated as an effective strategy for integrating electrical conductivity with the inherent properties of insulating fibers.

Certain fibers, such as polyacrylonitrile (PAN) and cellulose, can be rendered conductive through carbonization, a method commonly employed to fabricate high-performance carbon fibers[108,109]. For instance, Gupta et al. reported on the impact of carbonization temperature on the crystallinity and electrical conductivity of PAN fibers[110]. The conductivity of PAN fibers carbonized at 1,000, 1,800, and 2,200 °C increased monotonically from 5.32 to 51.01 S·m-1 and 75.91 S·m-1, respectively. Thus, by controlling the carbonization temperature, it is feasible to achieve fibers with the desired level of conductivity.

Additionally, electroless deposition and electrodeposition are also common methods for the surface functionalization of fibers[111-113]. Electroless deposition employs a potent reducing agent in a solution of metal ions to reduce the metal ions to their metallic form, which subsequently deposits onto the surface of materials[114,115]. Electrodeposition, referred to as electroplating, is a method of depositing a metal layer onto the surface of a material through electrolysis[116,117]. Both electroless deposition and electrodeposition have their respective advantages. The former does not require an external power source, and it can form a uniform coating on substrates of complex geometry, making it suitable for surface metallization of complex shapes or insulating materials[118,119]. The latter allows for the control of metal layer thickness and deposition rate, making it appropriate for applications requiring a thicker metal layer[120-123].

Inherently functional fiber making

Previous methods focused on surface treatment of insulating fibers to achieve functional fibers. Extensive experimental evidence has demonstrated that it is also feasible to produce inherently functional fibers through various processes, including thermal drawing, spinning, and 3D printing.

The thermal drawing technique, derived from the technology used in optical fiber fabrication, can also be employed to manufacture functional fibers[124]. Loke et al. have demonstrated the preparation of a preform integrating conductors, semiconductors, and polymer insulators, as depicted in Figure 3A[125]. Upon heating and stretching the preforms, the functional fiber exhibiting seamless material integration and exacting dimensional precision was achieved. Various methods can be employed for fabricating these preforms, including thin-film rolling for cylindrical fiber production, extrusion, lamination, drawing, and integrating different material components through hot pressing or advanced 3D printing technology[126]. Furthermore, various post-processing methods have been developed to overcome the mechanical property mismatch between different materials[127,128], such as laser and thermal annealing, as depicted in the second fiber of Figure 3A.

Textile electronics for ubiquitous health monitoring

Figure 3. Thermal drawing and various spinning techniques. (A) Thermal drawing[125]. Reprinted with permission. Copyright 2019, John Wiley and Sons; (B) Melt spinning[129]. Reprinted with permission. Copyright 2020, MDPI; (C) Dry spinning[134]. Reprinted with permission. Copyright 2018, John Wiley and Sons; (D) Wet spinning[138]. Reprinted with permission. Copyright 2014, American Chemical Society; (E) Dry-jet wet-spinning[141]. Reprinted with permission. Copyright 2023, MDPI; (F) Electrospinning[143]. Reprinted with permission. Copyright 2021, American Chemical Society; (G) Coaxial extrusion[144]. Reprinted with permission. Copyright 2018, American Chemical Society.

Spinning is a prevalent process for converting polymers into fibers, including melt spinning, wet spinning, dry spinning, dry-jet wet spinning, and coaxial extrusion. Melt spinning is a process that involves using the apparatus shown in Figure 3B to incorporate conductive fillers into easily meltable polymers or to blend conductive polymers with matrix polymers[129]. Common matrix polymers used in the spinning process include polypropylene (PP), PU, thermoplastic PU (TPU), and Ecoflex[130-132]. Probst et al. blended highly elastic TPU with conductive CNTs to fabricate conductive fibers via the melt-spinning process[132]. These fibers exhibit high elongation, mechanical properties comparable to conventional elastic fibers, and electrical conductivity on par with conductive liquid. Notably, melt spinning focuses on using the blends of conductive polymers with thermoplastic polymers suitable for this process due to the inadequate stability, toughness, and processability of pure conductive polymers[129,133].

Dry spinning is a method that usually uses hot gas to process the spinning solution for solidification. After the solvent evaporates, the polymer solidifies to form conductive fibers [Figure 3C][134]. For polymers and their solvents that are stable at high temperatures, dry spinning may be the preferred method. If the polymers are sensitive to high temperatures, such as PVC melt (melting point: ~80-85 °C), dry spinning is also possible under strict processing conditions. For those polymers that can be easily dissolved in a specific solvent but are not easily melted, wet spinning offers a suitable alternative. For instance, the cellulose acetate (melting point: ~160-190 °C) is dissolved in acetone (boiling point: ~56 °C) for fabricating a wet spinning solution[135-137]. First, a spinning solution containing conductive nanomaterials or conductive polymers is extruded through a spinneret into a coagulation bath. Subsequently, the solvent diffuses into the bath, facilitating the solidification and formation of conductive fibers [Figure 3D][138]. The earliest single-walled CNT (SWCNT) fibers were successfully assembled through wet spinning[139]. By adjusting parameters such as injection rate, flow speed, and the size of the needle or capillary tube, the morphology of the spun fibers can be controlled, allowing for the fibers with diameters ranging from a few micrometers to 100 μm. Eom et al. extruded a high-concentration MXene dispersion through a nozzle into a coagulation bath containing NH4Cl and NH4OH, forming a gel-like MXene fiber[140]. Subsequent post-treatment in a water bath yielded highly conductive MXene fibers with excellent electrical conductivity (7,713 S·cm-1) and good mechanical properties.

Additionally, the dry-jet wet spinning technology combines both dry and wet spinning characteristics. Unlike conventional wet spinning, in dry-jet wet spinning, the fine filament stream exits the nozzle and traverses a defined air gap without encountering any solidifying medium, as illustrated in Figure 3E. This intervention is beneficial for curtailing fiber stretching and enhancing fiber orientation[141]. Consequently, dry-jet wet spinning can significantly reduce solvent consumption, boost production efficiency, and is applicable to a broad spectrum of polymers, including those that present processing challenges in traditional wet spinning setups.

Electrospinning involves continuously drawing fibers using static electricity [Figure 3F][142,143]. Although electrospinning shares a reliance on solvent evaporation for fiber solidification with dry spinning, traditional dry spinning is limited in producing nanoscale fibers. Furthermore, advances in spinneret design have led to the development of coaxial extrusion techniques, such as coaxial electrospinning and coaxial wet spinning [Figure 3G][144,145]. Coaxial extrusion can create multi-layered fibrous structures, typically with a conductive layer at the core and an insulating layer as the sheath.

Moreover, 3D printing technology, with its exceptional design flexibility and manufacturing adaptability, enables on-demand customization. For example, composite fibers of boron nitride nanofiber/polyvinyl alcohol (BNNS/PVA) have been successfully produced via 3D printing, boasting high mechanical strength and excellent thermal conductivity[146]. The functional fibers can be further integrated into textiles with diverse structures for personal cooling applications. As shown in Figure 4A and B, the BNNS/PVA ink is continuously extruded through a metal needle into a methanol bath at 0 °C for cooling, forming a continuous printed fiber. In this process, PVA serves as a dispersing agent to achieve uniformly dispersed BNNSs, as shown in Figure 4C.

Textile electronics for ubiquitous health monitoring

Figure 4. (A) Schematic of the fabrication of as-printed fiber; (B) Photo image of 3D-printed fiber cooling in methanol; (C) Photo image showing DMSO/BNNSs dispersion and PVA/DMSO/BNNSs dispersion after standing for one week[146]. Reprinted with permission. Copyright 2017, American Chemical Society; (D) Schematic of the 3D printing process of coaxial functional fiber[147]. Reprinted with permission. Copyright 2021, Elsevier; (E) 3D printing procedure of different functional fibers for a sensor[148]. Reprinted with permission. Copyright 2017, John Wiley and Sons. DMSO: Dimethylsulfoxide; BNNSs: boron nitride nanofibers; PVA: polyvinyl alcohol.

Similar to the coaxial extrusion, coaxial fibers can also be prepared by 3D printing. As shown in Figure 4D, a conductive core ink is formulated by blending graphene powder with a PDMS prepolymer, while an insulating sheath ink is concocted by combining polytetrafluoroethylene (PTFE) particles with the same PDMS prepolymer. The core and sheath printing inks are extruded through the coaxial printing nozzle of the 3D printer. The printed fibers were heat-cured at 170 °C, and then highly elastic coaxial fibers with 300% strain were obtained[147]. Moreover, 3D printers can design various 3D shapes and even directly print a complete device[148,149]. Figure 4E shows the step-by-step process of 3D printing to fabricate a pressure sensor. In this process, a base layer was printed using silicone rubber. A sensing layer was printed using a composite material with specific silver content. The ratio of silver to polymer can be adjusted to achieve the desired conductivity and pressure sensitivity. The electrode layer was printed using a composite material with high Ag content to ensure optimal conductivity. An isolation layer was employed in the device to separate the sensing layer and the electrode layer. Notably, the support layer should be removed through hydrolysis after printing.

In general, the preparation of multifunctional fibers often requires the participation of various technologies. Consequently, in the specific preparation process, these technologies should be strategically selected and combined based on the actual requirements of the application.

Fabrication of functional fabrics

Functional fibers can be obtained using the fabrication techniques previously presented, preparing for the fabrication of yarns and fabrics. Four production stages are shown in Figure 5A, ranging from the initial fiber stage to the finalization of apparel products. As shown in Figure 5B, the classification of fabric structures is delineated into five distinct categories[150-153].

Textile electronics for ubiquitous health monitoring

Figure 5. (A) Production stages from fibers to products; (B) Summarization of various fabric structures. Figure “Weaving”[150], reprinted with permission. Copyright 2018, John Wiley and Sons; Figure “Kitting”[151], reprinted with permission. Copyright 2013, Elsevier; Figure “Stitching”[152], reprinted with permission. Copyright 2020, Elsevier; Figure “Braiding”[153], reprinted with permission. Copyright 2020, Springer Nature; (C) Woven structures obtained by individual functional fiber, complex fibers and carbonization, respectively. Figure (i)[168], reprinted with permission. Copyright 2017, Springer Nature; Figure (ii)[169], reprinted with permission. Copyright 2021, American Chemical Society; Figure (iii)[170], reprinted with permission. Copyright 2019, Elsevier.

Weaving is a prevalent technique for the integration of textile electronics into fabrics due to the minimal deformation that occurs during the weaving process[154,155]. Woven structures can be formed by vertically interweaving warp and weft threads through a loom, resulting in a fabric with a uniform texture, including plain, twill, satin, basket, leno, and mock leno[156-158]. The most popular woven structure is the plain weave due to its simplicity, minimal repeat dimensions, and ease of formation and identification[159]. This structure integrates various electronic components such as pressure sensors, strain sensors, circuit boards, logic operations, solar cells, etc.[51]. However, the precise control of the weft yarn presents a challenge for the positioning of microelectronic devices[160].

In the knitting process, yarns are formed into a looped structure through either mechanical knitting machines or manual knitting techniques[161,162]. Owing to their looped construction, fabrics with knitted structures exhibit high extensibility, enabling them to withstand external forces better[160]. Additionally, knitting makes it easy to obtain circular or tubular structures in a bi-layer configuration. It is beneficial for the fabrication of devices that require the integration of multiple materials in contact.

Stitching, a method that employs sewing threads to bind multiple layers of material, is employed to enhance the thickness, strength, and durability of fabrics[163,164]. This process not only significantly amplifies the reinforcing effect but also elevates the permanent recovery ratio[152]. Furthermore, braiding is a simple technique for intertwining three or more strands of yarn to create narrow strips or flat fabrics, used for rope, shoelaces, and net-shape composite preforms[153,165]. Furthermore, non-woven structures stand apart from traditional weaving or knitting. They are formed by fixing fibers together using adhesives, heat pressing, or electrospinning, resulting in anisotropic, inhomogeneous fabrics with porosity and permeability[41,166,167].

Regardless of the structures, functional fabrics can be formed by individual functional fibers/yarns, or by weaving functional fibers/yarns with insulating fibers/yarns, which are then made into garments. Moreover, the previously discussed techniques for the functionalization of insulating fibers, such as carbonization and deposition, are equally applicable to insulating fabrics. Taking the woven structure as an example, as shown in Figure 5C, the fabrication of functional fabrics can be achieved through weaving with individual functional fibers, weaving with different fibers, and carbonization[168-170].

DESIGN STRATEGIES OF TEXTILE HEALTH MONITORING SYSTEM

The design and fabrication of textile electronics constitute a complex endeavor, as they involve integrating electronic systems with a textile platform. A simple health monitoring system includes a power module, sensing module, interconnections, data processing module, communication module, and display module. In such integrated systems, the design of textile electronics necessitates well-considered manufacturing decisions, which involve selecting appropriate materials and processes to ensure adherence to design specifications under specific constraints.

Power module

The power module serves as the energy core of the system, providing the necessary power to other modules. The power management circuitry is responsible for voltage regulation, current control, and power distribution. Recently, beyond conventional commercial energy devices, a variety of textile-based energy harvesting and storage devices, such as solar cells, supercapacitors and batteries, has emerged.

The energy harvesting devices effectively capture ambient energy sources, including solar radiation, thermal gradients, mechanical vibrations, and kinetic energy from human motion, to power wearable health monitoring systems. They typically leverage specialized materials optimized for energy conversion, such as photovoltaic, triboelectric, piezoelectric, and thermoelectric materials, to achieve efficient energy management in wearable applications. The use of photovoltaic materials to create solar cells is the primary technology for solar power generation[171]. When two triboelectric materials come into contact and then separate, they generate electrical energy due to the triboelectric effect[172]. Additionally, piezoelectric materials generate an electric charge when subjected to mechanical stress, also leading to the production of electrical energy[173,174]. Furthermore, thermoelectric materials are capable of converting thermal energy into electrical energy, making them particularly useful for waste heat recovery or in environments with significant temperature differences[175].

When ambient energy is insufficient, energy storage devices become essential to maintain reliable operation of health monitoring systems. Critical factors in designing these devices include volume, weight, flexibility, safety, charge-discharge rate, and cycle life. For example, Li et al. demonstrated that zinc-ion batteries are highly suitable for textile applications due to their high theoretical capacity and low redox potential, making them effective for powering display modules[176]. In an intelligent health monitoring system, energy storage devices should be capable of working in tandem with energy harvesting systems to enable seamless transitions during periods of low energy supply.

Sensing module

The sensing module is designed to monitor various parameters related to physical health. Sensing fibers can be integrated into textiles to establish direct contact with the skin or other body parts. For textile-based pressure sensors, the working principle relies on the increased contact area between sensing fibers and electrode fibers, as well as the interactions between the sensor fibers themselves[177]. The contact and compression within and between the fibers lead to an increase in the conductive pathways, thereby enhancing the overall conductivity of the sensor. Additionally, the sensitivity of acoustic sensors to sound pressures and frequencies at various distances suggests the potential for harnessing energy from ambient noise and vibrations[178]. In addition, ultraviolet (UV)-sensitive textile electronics are mainly realized through materials that respond to UV exposure[179]. Temperature sensors can be created using temperature-sensitive materials as textile electrodes[180]. If the body’s electrolyte balance, kidney function, or breath odor needs monitoring, sensors can be designed to detect biochemical signals related to liquids or gases[181,182].

Interconnections

Textile-based sensors require connection to other circuit elements, additional sensors, and/or data acquisition circuits to function effectively. Therefore, flexible or rigid interconnects and connectors are critical to ensuring the functionality and durability of the final monitoring system. Interconnects are conductive pathways that link various textile electronics within or between textiles. These pathways can be made from conductive fibers, tracks printed with conductive inks, or other forms of conductive materials[70]. Typical interconnects found in textile electronics that are suitable for textile-based sensors are conductive yarns[40]. Connectors are physical interfaces used to connect conductive pathways in textiles to rigid electronic components, such as integrated circuits (ICs) and sensors. These connectors provide a reliable electrical connection between the softness of the textile and the rigidity of the electronic components. Connectors can be categorized into three types: physical connections (such as soldering and welding)[31], mechanical connections (such as gripping, crimping, and sewing)[183], or connections using conductive adhesives (such as conductive epoxy)[184,185]. Moreover, the electrodes in textile electronics, often integrated as conductive fibers or yarns, play a crucial role in the detection, collection, and transmission of signals[186]. The synergistic integration of the various textile electronics, electrodes, interconnects and connectors holds great promise for realizing a comprehensive textile-based health monitoring system.

Data processing module

The data processing module serves as the central component of the health monitoring system. After capturing the initial sensing signals, a signal conditioning circuit that includes amplifiers, filters, and analog-to-digital converters (ADC) is utilized to process these signals. Subsequently, the processed data is transmitted to the microcontroller for further analysis and processing.

This module is underpinned by a suite of algorithms that leverage statistical analysis, machine learning, and other sophisticated data analysis techniques to enhance the accuracy and efficiency of health monitoring protocols. In textile-based health monitoring systems, machine learning provides a range of powerful data analysis techniques. Compared to traditional data processing methods, machine learning can handle datasets with high complexity and multiple variables, which is critical for processing extensive health monitoring data. Algorithms such as support vector machines (SVM), convolutional neural networks (CNN), K-nearest neighbors (KNN), and decision trees can make predictions about new, unseen data after undergoing training. Although the data processing module is crucial, it often receives less attention in the literature compared to the more prominent sensing modules. Table 1 summarizes several machine learning algorithms utilized in textile-based health monitoring systems, providing a reference for the future development and optimization of new algorithms.

Table 1

Some machine learning algorithms for healthcare monitoring systems

TextileSensorFunctionMachine learning modelsRef.
FabricPressure sensorBiometric gait recognitionSVM[187]
Muscle pantsStretch sensorHuman motion recognitionRandom forest, neural network, SVM[188]
Chest bandStretch sensorTalking detectionRandom forest, neural network, linear discriminant analysis[189]
FabricGas sensorGas sensing identificationMachine learning-enabled principal component analysis[190]
VestTriboelectric sensorSitting position recognitionRandom forest[191]
CuffTriboelectric SensorCardiovascular monitoringNeural network[192]
Wristband, socksPressure sensorRespiration and gait recognitionCNN[193]
GarmentPolymer optical fiber sensorActivity classificationKNN classifier[194]
Knee covers, sleevesStrain sensorHuman motion recognition1D CNN[195]

Communication module

The function of the communication module is to realize the transmission and communication of health data. Communication modules can be categorized into two types based on transmission mode: wired and wireless. Wired communication modules, such as Ethernet, are ideal for scenarios demanding stable and high-speed data transfer. On the other hand, wireless communication modules, including Bluetooth, Wi-Fi, near field communication (NFC), and radio frequency identification, are suited for situations that call for mobility and flexibility in data transmission. Textile antennas, designed for the transmission and reception of radio waves, have garnered considerable research attention. To meet specific design requirements, the antenna’s geometry and dimensions are developed using electromagnetic simulation software to predict the performance of the antenna[196]. Subsequently, the conductive material is applied to the substrate material using printing technology (such as screen printing or inkjet printing) or coating technology to create the antenna[197].

Display module

To present visual health management and analysis, the collected monitoring data is transmitted to an external display device, such as a smartphone or computer interface. In recent years, preliminary display fabrics have been realized. There are two approaches to fabricating textile displays. The first approach involves directly manufacturing thin-film light-emitting diodes (LEDs) onto the fabrics. For optimal LED performance, it is essential that the underlying substrate is extremely smooth. Consequently, a critical step is applying a polymer buffer layer to the textile’s uneven surface through methods such as heat pressing or UV-induced photopolymerization[198,199]. Alternatively, light-emitting fibers can be created and then woven directly into the fabric to serve as displays[200,201]. The advancement of light-emitting fabrics for real-time health status display is anticipated to drive significant progress in health monitoring system development.

In summary, the design of all modules must consider compatibility, size, shape, and flexibility to facilitate their integration with textiles. The existing textile-based health monitoring systems still combine rigid and flexible components. Numerous challenges remain in the development of a fully textile-based health monitoring system.

APPLICATIONS OF TEXTILE ELECTRONICS IN HEALTH MONITORING

In health monitoring systems, textile electronics play an essential role, necessitating one or more such components. These fundamental components can be categorized into four types based on their functionality: sensors, displays, energy devices, and memory devices[160,202]. They are integrated with some commercial hardware and software to achieve a comprehensive health monitoring workflow. Notably, the applications introduced in this review are just a few emerging examples. The health monitoring systems based on textile electronics are rapidly evolving, and an increasing number of applications are expected to be developed. The integration of diagnostic and therapeutic capabilities in healthcare systems represents a future trend for the advancement of textile electronics.

Human motion monitoring

Currently, technologies for detecting human motion are predominantly divided into two principal categories: stationary and mobile monitoring. The stationary monitoring approach is contingent upon equipment positioned at designated sites, including depth cameras and far-infrared cameras. However, this approach has several limitations, including high costs, data accuracy, extensive data storage and processing, restricted monitoring range, and potential privacy concerns[14]. In contrast, mobile monitoring technologies facilitate the unrestricted movement of subjects within an environment, typically employing wearable sensing systems. In these systems, the application of textile electronics is revolutionizing the way of human motion monitoring. These intelligent textile electronics demonstrate high sensitivity to minute variations in tension or pressure. Moreover, they can be custom-tailored into various configurations and dimensions to meet the diverse requirements of human motion monitoring[203]. In human motion monitoring systems, textile electronics are integrated into the seams of garments to capture the movements of the limbs (such as the knees or elbows), and they can also be positioned on the dorsal region to monitor spinal posture and upper body position[191,204,205].

For instance, to motivate individuals with obesity or cardiovascular conditions to engage in increased physical activity, the development of lightweight and comfortable sensing textiles is imperative. These smart textiles can monitor their daily activity levels, providing a means to track progress and encourage a more active lifestyle[206]. Regarding Parkinson’s disease, although a complete cure is not possible, active treatment and management can help patients maintain a good quality of life and work capacity[207]. Precise measurement of their movements is crucial for assessing the effectiveness of treatment. By monitoring specific motion patterns, physicians can better understand the patient’s condition and adjust the treatment plan accordingly.

In clinical monitoring applications, textile electronics designed for human motion monitoring are integrated with motion analysis algorithms. In 2020, Lin et al. developed an innovative near-field responsive sensing network by integrating near-field relays, commercial NFC tags, wireless battery-free temperature and strain sensors, conductive threads, connections using conductive epoxy (CW2460, Chemtronics), and wireless readers[208]. This state-of-the-art wireless garment enables the real-time assessment of spinal posture and the continuous monitoring of body temperature and gait during the exercise period. In 2022, Jiang et al. used machine learning algorithms for the design of a self-powered posture monitoring vest (SPMV) integrating conductive fibers, nylon yarns, sensor array [triboelectric nanogenerators (TENGs)] with protection layer[191]. In addition, a step motor for periodic contact-separation movement and LabView and Python software platforms for real-time data processing are applied. Precise, real-time posture recognition and correction are achieved using the SPMV. Besides, the deployment of a random forest classifier has yielded an impressive accuracy rate of 96.6%, surpassing the accuracy of logistic regression and decision tree classifiers. In 2023, the same research group developed a self-powered multi-point body motion sensing network (SMN) based on a fully textile structure, enhancing pressure response sensitivity and breathability [Figure 6A][187]. Similar to their previous study, the body motion sensing system consists of a sensing fabric, a linear motor, and a human-computer interface platform based on LabView software. The sensing fabric was fabricated using Ag-polyethylene core-sheath composite yarns through 3D knitting techniques, ensuring each sensing node exhibits high linear sensitivity to pressure. Additionally, a SVM algorithm was integrated into the SMN for processing the sensory data [Figure 6B]. By analyzing the time series and dynamic parameters of five deformed gaits [Figure 6C], gait recognition and classification with an accuracy rate of 96.7% are effectively achieved [Figure 6D]. Constructing a real-time human-computer interaction platform based on the SMN holds the potential to assist in the diagnosis of neurological disorders, such as Parkinson’s disease and dystonia.

Textile electronics for ubiquitous health monitoring

Figure 6. (A) The structure of SMN for body motion sensing. The sensitivity of the SMN is 1.56 V·kPa-1 under pressure below 2 kPa; (B) SVM classifier for gait recognition and auxiliary rehabilitation training; (C) Multi-channel test results of five deformed gaits containing PG, SG, MG, GG, and CG; (D) Classification accuracy of five gaits using different machine learning algorithms[187]. Reprinted with permission. Copyright 2023, John Wiley and Sons; (E) The working process of an epilepsy treatment system; (F) In vivo experiment to relieve epileptic seizures in mice; (G) Total epileptic seizure duration under two conditions; (H) The mean epileptic seizure number during 0-120 min under two conditions[210]. Reprinted with permission. Copyright 2023, Elsevier. SMN: Self-powered multi-point body motion sensing network; SVM: support vector machines; PG: Parkinson’s gait; SG: scissors gait; MG: mopping gait; GG: gluteus maximus gait; CG: cross-threshold gait.

In everyday scenarios, human limbs may exhibit vibrations at approximately 1-3 Hz, whereas epileptic seizures are characterized by vibrations at varying frequencies, reaching up to 7 Hz[209]. Therefore, it is possible to distinguish between the signals of normal movement and epileptic seizures by analyzing the frequencies associated with different human behaviors. A self-powered, wearable epilepsy monitoring system for potential epilepsy treatment is shown in Figure 6E[210]. This system is capable of real-time monitoring of human motions and delivering neural stimulation signals to mitigate epileptic seizures. In this system, the energy harvesting module converts mechanical energy generated from human motions into electrical energy, with the rectifier subsequently charging the capacitors. The motion detection sensor detects subtle human motions and transmits signals to the data processing center. The data processing center can identify epileptic seizures and generate neural stimulation signals. As shown in Figure 6F, the system operation successfully suppressed the epilepsy of the mouse. By stimulating the dentate gyrus of the mouse with a stimulation electrode, the total duration of epileptic seizures in the mouse can be reduced by 40%-50% [Figure 6G and H].

The research findings highlighted the potential of merging textile electronics for human motion monitoring. With the assistance of AI algorithms, a motion monitoring system based on textile electronics is equipped to offer personalized health advice and exercise prescriptions to individuals.

Physiological monitoring

Textile electronics have revolutionized the conventional rigid design of physiological monitoring devices, enabling the development of textile electronics that provide real-time, continuous, non-invasive, and comfortable monitoring of vital physiological signals[211]. These devices stand out for their efficacy in monitoring chronic conditions, including cardiovascular diseases and diabetes[192,212]. To intuitively understand the applications of textile electronics in physiological monitoring over the past five years, Table 2 presents a comprehensive overview of physiological monitoring devices with the materials employed, the fabrication techniques utilized, the product developments realized, and the monitoring locations.

Table 2

Summary of representative physiological monitoring devices in the past five years with materials, preparation methods, products and monitoring location

SignalsMaterials/componentsFabricationProductsMonitoring
location
SEISNR/sensitivityRef.
ECGAg-plated fibersElectrostatic flockingT-shirtChestA few hundred kΩ at 100 Hz and 1,000 Pa/[213]
ECGAg/M-PETFElectroless depositionT-shirtChest//[214]
ECGAg/AgClScreen printingPolyester fabricHand and legA few hundred Ω within 100 Hz/[215]
ECG/EMGrGO, sericin, water retention polymerKnittingSports undergarment, sleeveRA, RL, LL24 kΩ at 1,000 Hz35-40 dB at pH = 4.3[216]
ECGFabink-TC-C4001, MOS TitanRFScreen printingMattressBack~200 kΩ at 10Hz; 50 kΩ at 100-1,000 Hz-40 dB[217]
EMGGrapheneDip-coatingSleeveArms and legs~90 kΩ at 1-5 Hz19.23 dB[218]
EMGPEDOT:PSSScreen printingSleeveLegs3-20 kΩ at 30 Hz/[219]
EEGAg flakes/SISScreen printingHeadbandForehead< 10 kΩ-32.7 dB[220]
EEGAgKnittingCapHead5-30 kΩ at 0.1-30 Hz33.6 dB[221]
EOGGrapheneDip-coatingHeadbandForehead//[183]
ECG/EOGLIG, AgCl, carbon inksScreen printingFabricForehead~700 Ω at 0.1-500 Hz/[222]
EEG/EOGAgKnittingHeadbandForehead//[223]
TemperaturePolycarbonate, battery, thermistorsThermal drawingDigital fiber, T-shirtBody//[224]
TemperaturePEDOT:PSS, PU/grapheneWet spinning, weavingFabricArm/-1.72%/°C[225]
TemperatureThermal-sensitive ink PDMSEtching, coatingFabricLower limb/62.3 V/K[226]
Respiratory RateFunctional yarnsWrappingMaskFace/82.4 pF/% RH[227]
Respiratory RateAg NPsDrop castingChest strapChest/0.043[228]

ECG represents a medical diagnostic technique designed to capture the electrical activity of the heart. Unlike the mechanical vibration sensing of acoustic sensors, ECG sensing is adept at detecting alterations in the action potentials of cardiomyocytes. The integration of textile electrodes has become the cornerstone for ECG monitoring, allowing for a more comfortable and continuous assessment of cardiac activity. In an early study[229], emulating the traditional Yuzen dyeing technique of Japanese kimono, researchers employed PDMS as a template to directly imprint conductive polymer patterns of PEDOT:PSS onto textiles, as illustrated in Figure 7A. The textile electrodes were utilized for ECG recordings with the SandsResearch system (EA68 or EA136 amplifiers) and a data processing module (LabView software). The realization of the precise tracking of cardiac activity in motion [Figure 7B] and good stability in ambient air [Figure 7C] represents a significant development to textile electronics for ECG monitoring applications.

Textile electronics for ubiquitous health monitoring

Figure 7. (A) Process of PEDOT:PSS coating on textiles; (B) Percentage of accuracy of heartbeat detection for five human behaviors; (C) Evolution of ECG signals over time[229]. Reprinted with permission. Copyright 2015, Springer Nature; (D) Schematic illustration of the measuring process for EMG signals and the testing postures[230]. Reprinted with permission. Copyright 2023, Springer Nature; (E) Skin-to-electrode impedance condition of different EEG electrodes over time; (F) Schematic illustration of the EEG measurement system [231]. Reprinted with permission. Copyright 2021, IEEE; (G) Photograph of an EOG headband; (H) EOG trace showing the different types of eye movement[183]. Reprinted with permission. Copyright 2019, IOP Science. PEDOT:PSS: Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); ECG: electrocardiograms; EMG: electromyography; EEG: electroencephalographic; EOG: electrooculogram.

EMG signals are typically acquired from the arms or legs [Table 2]. For instance, muscle activity monitoring using a leg sleeve for detecting EMG signals is illustrated in Figure 7D[230]. For EMG recordings, the textile electrodes and reference electrodes were connected to a wireless EMG acquisition system that included a wireless transmitter and a BIOPAC system with a wireless receiver. Then, the results were shown on the user terminal through an Ethernet connection. Moreover, an investigation into embroidery techniques for textile electrodes found that the moss stitch method produced a lower skin-electrode impedance (SEI) than the lock stitch method. SEI, or the resistance at the skin-electrode interface, is crucial for efficient signal transmission and high accuracy, which is mainly reflected in the signal-to-noise ratio (SNR). Thus, the moss stitch method enhances reliable EMG signal acquisition.

Electroencephalographic (EEG) signals capture the electrical activity of the brain, playing a crucial role in the diagnosis of neurological disorders such as epilepsy, sleep disorders, and brain injury. Tseghai et al. developed washable and flexible textile electrodes for detecting EEG signals emanating from cerebral activity[231]. The textile electrodes demonstrate lower SEI compared to conventional Ag/AgCl dry electrodes after three minutes [Figure 7E] due to sweat permeating the textile, rendering them highly suitable for long-term EEG monitoring applications. In Figure 7F, three textile electrodes and two reference electrodes are connected to a battery and an OpenBCI board to record EEG waveforms. The EEG signals are then displayed on a laptop using the OpenBCI GUI software via a Bluetooth module. Notably, these textile electrodes enable skin contact without the requirement for conductive gels and exhibit robust stability in EEG signal acquisition, even following multiple wash cycles and bending.

Electrooculogram (EOG) records the electrical activity linked to eye movements, serving as a valuable diagnostic tool for investigating the visual system and analyzing sleep patterns. As shown in Figure 7G, a smart headband using graphene is used for EOG signal monitoring. The graphene textile electrodes are secured in an elastic headband with adhesive foams by a metallic snap fastener. The EOG-based human-computer interaction interface is obtained by a front-end readout circuit and a smart headband for signal acquisition, a microcontroller unit for processing signals, and a laptop computer for display. Furthermore, an automated algorithm has been developed to detect and classify ocular movements [Figure 7H]. The integration of the algorithm with the bright headband has expanded its applications in human-computer interaction and human-machine interfaces, achieving impressive recognition accuracies ranging from 85% to 100%.

Additionally, variations in human body temperature are indicative of metabolic activity and can reflect pathophysiological information[226,232]. Zhang et al. fabricated a thermosensitive micro/nanoporous fiber with an unprecedented high thermal sensitivity (β = 4,994.55 K, α = -5.58%/K at 26 °C) and the fastest response/recovery times (97/239 ms) recorded for textile-based temperature sensors[233]. The fiber was achieved by growing Fe2(MoO4)3 nanostructures on graphene using a wet spinning method. Compared to the conventional direct mixing of Fe2(MoO4)3 and graphene, the fibers produced by this method exhibit enhanced thermal sensing performance. The core thermoresistive micro/nanoporous fiber strand acts as both the temperature sensor and the working electrode of the textile TENG. The output signals are displayed on a mobile phone screen through a wireless system that includes an analog-to-digital conversion module, Bluetooth, and an accompanying app. Ultimately, real-time wireless monitoring of body temperature and pulse is achieved through textile electronics.

Respiratory rate, a vital sign, varies with age, health status, and activity levels. Anomalies in respiratory rate could be symptomatic of various conditions, including cardiac, pulmonary, metabolic disorders, or infections[234]. In respiratory rate monitoring systems, the humidity sensors[227] and pressure sensors[235] are fundamental and critical components. For instance, Lin et al. developed a pressure sensor based on ultrasoft helical functional fibers, demonstrating high sensitivity (1.726 V/N) and rapid response time (20 ms)[236]. They have successfully developed a real-time respiratory monitoring system, which includes a pressure sensor, an analog-to-digital conversion module, and a signal processing unit, and utilizes LabView software for further data processing. The system can continuously record vital parameters such as respiratory intensity, frequency, and intervals.

Biochemical monitoring

Sweat, as a biological fluid, provides a wealth of health-related biomarkers[237-239]. The rapid production and renewal rate of sweat implies that it can provide nearly real-time information on physiological status[240]. Therefore, long-term continuous monitoring of sweat can help track the trend of individual health status changes and detect abnormalities in time.

Recently, Li et al. developed a Janus nanoprocessed electronic textile (JNET) for comfortable sweat monitoring[241]. By combining radiative cooling with moisture-wicking capabilities, substantial enhancements in wearing comfort have been realized [Figure 8A]. The structure of JNET, as shown in Figure 8B, involves weaving different fiber sensors to detect various substances in sweat. The novel integration of the optimized substrate and sensing fibers ensures a comfortable physiological microenvironment for sweat monitoring under sweating and hot conditions. Compared with traditional fabrics, experimental results have shown that Janus nanoprocessed silk (JNPS) achieves significant cooling effects and reduces skin surface humidity [Figure 8C]. Figure 8D demonstrates that the textile electronics can simultaneously detect pH, uric acid (UA), and Na+ biomarkers. In practical applications, the JNET is connected to a printed circuit board (PCB) via fiber electrodes. The PCB primarily consists of an MS02 chip, Bluetooth module, power supply, and other functional modules, enabling the real-time wireless transmission of sensing signals to be displayed on a smartphone [Figure 8D].

Textile electronics for ubiquitous health monitoring

Figure 8. (A) JNET with function of radiative cooling and anisotropic wettability; (B) The JNET is fabricated by different functional fibers and exhibits high sensitivity: 81.03 mV·pH-1 for pH, 0.08 μA/μM for UA, and 108.93 mV/decade for Na+; (C) Comparison of hygroscopic properties between pristine silk and JNPS; (D) The results of real-time sweat monitoring by JNET[241]. Reprinted with permission. Copyright 2023, Elsevier; (E) Schematic illustration of a fabric sensor for cortisol monitoring, with a detection limit of 1 pM for cortisol; (F) Design of an integrated system containing a biosensing module, FPCB module, Energy module and display module; (G) Different stages of stress monitoring and management[49]. Reprinted with permission. Copyright 2024, John Wiley and Sons. JNET: Janus nanoprocessed electronic textile; UA: uric acid; JNPS: Janus nanoprocessed silk; FPCB: flexible printed circuit board.

Additionally, cortisol can be detected in sweat, correlating with the stress levels experienced by individuals. Hu et al. developed textile electronics based on CNT fibers for populations troubled by depression[49]. In the research, Prussian blue as an oxidation-reduction probe was deposited onto molecularly imprinted polymers (MIP) to directly detect cortisol upon contact with sweat. As shown in Figure 8E, the textile includes three functional fibers. MIP/CNT fiber serves as the working electrode, while Ag/AgCl/CNT fiber and Pt/CNT fiber act as the reference and counter electrodes, respectively. Then, the integrated textile electronics and other modules of a complete sweat monitoring system are illustrated in Figure 8F. The sweat sensor converts variations in cortisol concentration into electrical signals, which are subsequently transmitted to the flexible PCB for data processing. These signals are amplified, filtered, and converted into readable data, and then sent to the display module via a wireless module (such as Bluetooth). Users can view real-time monitoring reports of cortisol through the user interface (UI). An application scenario of real-time stress management is shown in Figure 8G. After the stress test, the cortisol levels of participants gradually decrease. If participants exercise, their cortisol levels will also decrease after exercise.

Multifunctional health monitoring system

Conventional health monitoring systems with single-function monitoring are inadequate for some special situations, such as pregnancy and sleep monitoring that necessitate simultaneous tracking of various human motions and physiological signals[44,226]. Hence, the necessity for multifunctional health monitoring systems arises to meet the intricate demands of such scenarios[242-244]. In this section, a multifunctional health monitoring system for sleep monitoring as an example is discussed.

Lin et al. developed a smart mattress based on pressure-sensitive TENG arrays for real-time monitoring of sleep behaviors[42]. The smart mattress is constructed with conductive fibers and elastic materials, exhibiting high sensitivity, rapid response time, durability, and waterproof performance. The configuration of the sensor array is illustrated in Figure 9A, with individual addressing for each TENG unit. The conductive fibers are linked to the signal amplifier via the row/column data bus. The amplified signals are subsequently transmitted to the analog multiplexer and then fed into the ADC The microcontroller receives the digital signals from theADC for further processing. As the scanning progresses from the first row to the ith column, an i × j pressure image is constructed. This sequence of images forms a continuous data stream, which is subsequently transmitted to an external device such as a medical terminal or a personal mobile phone via the Bluetooth module.

Textile electronics for ubiquitous health monitoring

Figure 9. (A) Multi-channel data acquisition system for sleep state monitoring. One pixel corresponds to one TENG unit with a pressure sensitivity of 0.77 V·Pa-1; (B) The UI showing sleep states information including posture, position, and pressure distribution; (C) The diagram showing the press number distribution of a sleeper throughout the night; (D) Automatic warning function of smart bedsheet; (E) Auxiliary warning function of smart bedsheet[42]. Reprinted with permission. Copyright 2017, John Wiley and Sons; (F) Schematic illustration of a smart bedsheet integrated functional fibers with a high sensitivity of 10.79 mV·Pa-1; (G) Design of an integrated system containing sensing array, signal amplifiers, multi-channel processing, ADC, Bluetooth transmitter, and mobile terminal; (H) The flowchart of the obstructive sleep apnea-hypopnea syndrome monitoring and intervention system; (I) Photograph showing the patient is awakened by the system in abnormal situations[243]. Reprinted with permission. Copyright 2020, Elsevier. TENG: Triboelectric nanogenerator; UI: user interface; ADC: analog-to-digital converters.

When a user lies on the smart mattress, the body posture, position, and pressure distribution can be visualized on the graphical UI, as shown in Figure 9B. Figure 9C illustrates the distribution of pressure values for a sleeper throughout the night, indicating the sleep quality. In addition to sleep monitoring, the intelligent textile can serve as a fall warning system for the elderly or patients. If an elder or patient falls from the bed, signals from five TENGs along the edge of the mattress are sent to a computer or mobile terminal, triggering an alarm signal [Figure 9D]. Besides, they can autonomously call for help by touching the TENG in the upper left corner of the mattress when experiencing discomfort, thereby alerting family members or healthcare professionals [Figure 9E]. These advancements carry significant implications for remote healthcare.

However, multi-layered electronic fabrics can increase the weight of the detection system. Recently, the same group optimized the textile electronics. They first prepared a single functional fiber, and then multiple fibers were woven into a black textile substrate with a serpentine structure design, ultimately creating a single-layer, ultra-soft intelligent bedsheet [Figure 9F]. The operation of the monitoring system is shown in Figure 9G. Similar to their previous study, the pressure signals generated by each sensing unit are independently addressable and can be recorded through a customized multi-channel data acquisition circuit. After analog-to-digital conversion, the electric signals are transmitted to a mobile terminal via Bluetooth. The real-time images of sleep postures and various physiological signals are shown on mobile terminal displays.

Furthermore, the group also designed an obstructive sleep apnea-hypopnea syndrome monitoring and intervention system and demonstrated its reliability [Figure 9H]. In cases where the apnea duration exceeds a predetermined threshold, an alarm is activated immediately [Figure 9I]. Compared with their previous study, this monitoring system has demonstrated advancements in enhancing monitoring accuracy, broadening the scope of surveillance, and improving user comfort. In addition to tracking sleep posture and behavior, it has further expanded to include the monitoring of respiratory rate and heart rate.

INTEGRATION OF TEXTILE HEALTH MONITORING SYSTEM

Integration strategies

If fiber- or yarn-based sensors and LEDs are employed in the sensor module and display module, they can form multiple sensing and display pixels through the previously described five textile structures. However, if other flexible electronic devices are integrated into textiles, two connection steps require attention: the mechanical connection with the textile material and the electrical connection integrated into the conductive structure. Both connections must be functionally reliable. The mechanical connection involves securely attaching electronic components to the textile, considering the stability and durability of the connection while ensuring the softness and comfort of the textile. Mechanical connections can be achieved through sewing, adhesive bonding, or other textile processing techniques, similar to traditional ICs and multifunctional devices on two-dimensional wafers. Currently, limitations on scaling down and challenges in electronic circuit configuration remain significant obstacles.

Recently, Hwang et al. proposed a technology for integrating electronic devices such as transistors, inverters, ring oscillators, and thermocouples onto the outer surface of a one-dimensional microfiber substrate, as shown in Figure 10A[245]. Using capillary-assisted coating methods and high-resolution maskless lithography techniques, multiple micro-devices can be rapidly integrated onto a very narrow and thin fiber surface. Subsequent evaluations of the electronic characteristics of the micro-devices on the fiber included assessments of switching and data processing capabilities, as well as units for sensing or converting light and thermal signals. Test results indicate that this mechanical connection technology provides the device with good stability and flexibility, presenting a viable strategy for manufacturing high-density electronic microfibers.

Textile electronics for ubiquitous health monitoring

Figure 10. (A) Integration of multiple electronic components on a microfiber[245]. Reprinted with permission. Copyright 2022, Springer Nature; (B) The process of in-textile photolithography technology[247]. Reprinted with permission. Copyright 2024, Springer Nature; (C and D) The process of NIT and NIT-type IC[51]. Reprinted with permission. Copyright 2021, Springer Nature. NIT: Non-printed integrated-circuit textile; IC: integrated circuit.

Notably, while functional fiber assembly has advanced, current wireless modules and microelectronics still rely on silicon chips and batteries, which are bulky and rigid, adversely affecting textile functionality and comfort. Yang et al. addressed this challenge by proposing a human body coupling energy interaction mechanism for smart fibers, enabling wireless signal transmission via environmental electromagnetic energy[246]. By integrating an electrostatic-sensitive photoelectric medium, these fibers consolidate sensing and actuation, allowing for light-emitting displays and touch interaction without the need for chips or batteries, thereby offering a novel integration strategy for textile health monitoring systems.

To establish electrical connections in textiles, PCBs play a crucial role. Over the past two years, Wang et al. have reported innovative fabrication methods for creating circuit patterns on textiles, specifically double-sided photolithography technology and in-textile photolithography technology[247]. The latter represents an optimization of the former, enabling the fabrication of finer metal patterns (sub-100 µm) that can penetrate the interior of the textiles. This advancement maintains the three-dimensional porous structure of the textiles, thereby preserving their breathability and comfort [Figure 10B]. The optimized circuit patterns have been utilized to construct a multiplex sweat sensing system fully integrated into the textile framework, successfully monitoring physiological signals.

Additionally, Yang et al. prepared a non-printed integrated-circuit textile (NIT) for biomedical and therapeutic diagnostic applications[51]. This system comprises devices such as transistors, sensors, diodes, solar cells, and batteries, all constructed in the form of fibers or crossover nodes [Figure 10C]. These devices are woven into a deformable textile IC [Figure 10D]. The NIT employs fiber-based transistors for logic operations, incorporates various sensors for health and environmental monitoring, and integrates photovoltaic and battery fibers for self-powered energy. Wireless data transmission is facilitated via infrared or advanced communication fibers. The NIT represents a fully self-powered, wearable monitoring system, simulating an AI “nurse” for health oversight and emergency assistance. This non-printing approach offers a novel manufacturing process distinct from traditional PCBs, promising for future wearables and personalized healthcare.

Security and reliability of the components

The safety of textile-based health monitoring systems encompasses two primary aspects: human safety and environmental friendliness, as well as data security and privacy protection. Given that health monitoring devices are intended for integration on the human body or even for implantation, the functional fibers and fabrics must be non-toxic and harmless at a cellular level. Materials that are green, harmless, and environmentally friendly should be prioritized. Devices implanted in biological tissues must exhibit excellent biocompatibility to prevent scarring and inflammation.

In the data processing module, UI, and software, devices should undergo regular calibration to maintain data accuracy. In accordance with data protection regulations, such as the General Data Protection Regulation[248], personal health information should be encrypted for storage and transmission. Access control measures should be implemented to ensure that only authorized users can access sensitive data. To guard against cyber-attacks, firewalls and intrusion detection systems should be employed to enhance data security.

As textile electronics continue to evolve, future health monitoring systems are expected to develop into more powerful telemedicine solutions and smart wards. Therefore, for systems closely linked to medical care, the entire system design must comply with the safety and reliability standards of medical devices, such as obtaining Food and Drug Administration (FDA) approval[249].

CONCLUSION AND OUTLOOK

Textile electronics hold substantial potential for development in the field of wearable health monitoring. This review provides an overview of the materials and fabrication methods associated with textile electronics. Key design strategies for developing textile-based health monitoring systems are discussed. Furthermore, the applications of textile electronics in ubiquitous health monitoring are also introduced, including human motion monitoring, physiological monitoring, biochemical monitoring, and multifunctional monitoring. Moreover, current strategies for integrating health monitoring systems are explored, along with the security and reliability of their components. Despite the significant advancements made in textile-based health monitoring systems over the past two decades, considerable challenges remain to be addressed, spanning from material selection to system integration and eventual commercialization.

Performance improvement

In the development of textile electronics, active substances are typically endowed with specific functions through deposition onto textile substrates or polymer fibers. However, material compatibility issues may result in weak interactions at the interface between these active substances and their carriers, leading to a tendency for the active substances to detach under mechanical stress such as bending, stretching, or washing. This detachment adversely affects the operational stability of textile electronics. To enhance stability and durability, comprehensive optimization of material selection, fabrication processes, and textile structures is essential. For instance, improving coating techniques or utilizing more compatible binders can strengthen adhesion between active substances and fiber substrates, thereby enhancing the reliability of textile electronics during prolonged use. Additionally, the stability of energy storage fibers warrants attention, as passivation of electrode surfaces and biological contamination can lead to erroneous operational responses.

Integration

The integration of textile electronics is a pivotal step in achieving a multifunctional and efficient health monitoring system. Through integration, a variety of functionalities such as energy harvesting, signal processing, data storage, and wireless communication can be realized on a compact and wearable platform. Reliable connection technologies and textile-compatible ICs contribute significantly to the high degree of integration within electronic textiles. Although some integration technologies have been discussed in previous sections, there remains substantial room for improvement in the current level of integration compared to the demands of practical applications. Therefore, developing more effective integration strategies is essential for achieving high-performance textile electronics.

Large-scale fabrications

Industry reports indicate that numerous enterprises have developed a variety of smart textile electronics. Examples include Sergers heat socks designed for alpine skiing, Skin brand underwear capable of recording real-time heart rate, resting heart rate, and heart rate variability, and Siren’s washable smart socks tailored for individuals with diabetes. However, the manufacturing of these electronic textile products remains largely confined to laboratory settings. To facilitate commercial application, a transition to industrial-scale production is imperative. This transition necessitates not only the development of manufacturing technologies suitable for mass production but also considerations of cost-effectiveness. Laboratory-level manufacturing often fails to meet the cost and efficiency demands of large-scale production. Industrial manufacturing must address issues such as automation, standardization, and quality control. Additionally, the development of textile machinery adapted for functional fibers is crucial for realizing mass production. For instance, traditional textile machinery may require modification or redesign to accommodate the production of new types of textile electronics.

Health delivery

From a user-centric perspective, textile electronics must be sufficiently resilient to withstand regular use, including daily wear and washing, and yet remain comfortable and unobtrusive for patients. Therefore, standardized guidelines for the deployment and maintenance of these systems are essential. For these devices to be widely adopted in healthcare, they must comply with regulatory standards for medical devices, such as those established by the FDA. Furthermore, user adoption plays a crucial role in health delivery effectiveness. Patients may require training on proper use and maintenance of these wearable textiles, and healthcare providers must adapt to new patient data streams generated by these systems. Addressing these challenges can contribute significantly to improved patient outcomes and the efficient delivery of care resources.

To sum up, the advancement of textile electronics necessitates collaborative efforts from researchers across multiple disciplines, including materials science, textile engineering, electronic engineering, and biomedical engineering. By consistently overcoming pivotal material and technical challenges, future textile electronics will possess the capacity to integrate diverse functionalities and establish a closed-loop medical care system that delivers personalized, real-time, and comprehensive health management services. This progress not only fosters innovation in the healthcare sector but also enhances convenience and well-being in the daily lives of individuals.

DECLARATIONS

Authors’ contributions

Wrote the original draft: Huang FC

Supervised, reviewed, and revised the manuscript: Pan LJ, Shi Y, Sun XD

Availability of data and materials

Not applicable.

Financial support and sponsorship

This work was supported by the National Key Research and Development Program of China under Grant 2021YFA1401100 and the National Natural Science Foundation of China under Grant 61825403 and 61921005.

Conflicts of interest

All authors declared that there are no conflicts of interest.

Ethical approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Copyright

© The Author(s) 2024.

REFERENCES

1. Ahmed A, Sharma S, Adak B, et al. Two-dimensional MXenes: new frontier of wearable and flexible electronics. InfoMat 2022;4:e12295.

2. Sasmal A, Arockiarajan A. Recent progress in flexible magnetoelectric composites and devices for next generation wearable electronics. Nano Energy 2023;115:108733.

3. Yun J. Recent progress in thermal management for flexible/wearable devices. Soft Sci 2023;3:12.

4. Xi Y, Tan P, Li Z, Fan Y. Self-powered wearable IoT sensors as human-machine interfaces. Soft Sci 2023;3:26.

5. Gu Y, Zhang T, Chen H, et al. Mini review on flexible and wearable electronics for monitoring human health information. Nanoscale Res Lett 2019;14:263.

6. Butt MA, Kazanskiy NL, Khonina SN. Revolution in flexible wearable electronics for temperature and pressure monitoring - a review. Electronics 2022;11:716.

7. Sun G, Wang P, Jiang Y, Sun H, Meng C, Guo S. Recent advances in flexible and soft gel-based pressure sensors. Soft Sci 2022;2:17.

8. Zhu P, Li Z, Pang J, He P, Zhang S. Latest developments and trends in electronic skin devices. Soft Sci 2024;4:17.

9. Shi J, Liu S, Zhang L, et al. Smart textile-integrated microelectronic systems for wearable applications. Adv Mater 2020;32:e1901958.

10. Wei X, Liang X, Meng C, Cao S, Shi Q, Wu J. Multimodal electronic textiles for intelligent human-machine interfaces. Soft Sci 2023;3:17.

11. Heo JS, Eom J, Kim YH, Park SK. Recent progress of textile-based wearable electronics: a comprehensive review of materials, devices, and applications. Small 2018;14:1703034.

12. Zhu C, Wu J, Yan J, Liu X. Advanced fiber materials for wearable electronics. Adv Fiber Mater 2023;5:12-35.

13. Fang C, Xu B, Li M, Han J, Yang Y, Liu X. Advanced design of fibrous flexible actuators for smart wearable applications. Adv Fiber Mater 2024;6:622-57.

14. Sheng F, Zhao C, Zhang B, Tan Y, Dong K. Flourishing electronic textiles towards pervasive, personalized and intelligent healthcare. Soft Sci 2024;4:2.

15. Yin J, Wang S, Di Carlo A, et al. Smart textiles for self-powered biomonitoring. Med X 2023;1:1.

16. Yu H, Zhang S, Lian Y, et al. Electronic textile with passive thermal management for outdoor health monitoring. Adv Fiber Mater 2024;6:1241-52.

17. Wang P, Liu G, Sun G, Meng C, Shen G, Li Y. An integrated bifunctional pressure‒temperature sensing system fabricated on a breathable nanofiber and powered by rechargeable zinc–air battery for long-term comfortable health care monitoring. Adv Fiber Mater 2024;6:1037-52.

18. Wicaksono I, Tucker CI, Sun T, et al. A tailored, electronic textile conformable suit for large-scale spatiotemporal physiological sensing in vivo. Npj Flex Electron 2020;4:5.

19. Du K, Lin R, Yin L, Ho JS, Wang J, Lim CT. Electronic textiles for energy, sensing, and communication. iScience 2022;25:104174.

20. Li T, Qiao F, Huang P, et al. Flexible optical fiber-based smart textile sensor for human–machine interaction. IEEE Sensors J 2022;22:19336-45.

21. Wang W, Yu A, Liu X, et al. Large-scale fabrication of robust textile triboelectric nanogenerators. Nano Energy 2020;71:104605.

22. Seyedin S, Carey T, Arbab A, et al. Fibre electronics: towards scaled-up manufacturing of integrated e-textile systems. Nanoscale 2021;13:12818-47.

23. Gopalsamy C, Park S, Rajamanickam R, Jayaraman S. The Wearable MotherboardTM: the first generation of adaptive and responsive textile structures (ARTS) for medical applications. Virtual Real 1999;4:152-68.

24. Zhang L, Wang Z, Volakis JL. Textile antennas and sensors for body-worn applications. IEEE Antennas Wireless Propag Lett 2012;11:1690-3.

25. Mokhtari F, Spinks GM, Fay C, et al. Wearable electronic textiles from nanostructured piezoelectric fibers. Adv Mater Technol 2020;5:1900900.

26. Wang B, Facchetti A. Mechanically flexible conductors for stretchable and wearable E-skin and E-textile devices. Adv Mater 2019;31:e1901408.

27. Rao S, Llombart N, Moradi E, et al. Miniature implantable and wearable on-body antennas: towards the new era of wireless body-centric systems [antenna applications corner]. IEEE Antennas Propag Mag 2014;56:271-91.

28. Wang Z, Zhang L, Volakis J. Textile antennas for wearable radio frequency applications. TLIST 2013;2:105-12. Available from: http://api.semanticscholar.org/CorpusID:56475623. [Last accessed on 25 Nov 2024]

29. Vigo TL. Intelligent fibrous materials. J Text Inst 1999;90:1-13.

30. Park S, Jayaraman S. Smart textiles: wearable electronic systems. MRS Bull 2003;28:585-91.

31. Post ER, Orth M, Russo PR, Gershenfeld N. E-broidery: design and fabrication of textile-based computing. IBM Syst J 2000;39:840-60.

32. Bourdon L, Coli S, Loriga G et al. First results with the wealthy garment electrocardiogram monitoring system. In: Computers in Cardiology, 2005; 2005 Sep 25-28; Lyon, France. IEEE; 2005. pp. 615-8.

33. Bonderover E, Wagner S. A Woven inverter circuit for e-textile applications. IEEE Electron Device Lett 2004;25:295-7.

34. Cherenack K, van Pieterson L. Smart textiles: challenges and opportunities. J Appl Phys 2012;112:091301.

35. Paradiso R, Loriga G, Taccini N, Gemignani A, Ghelarducci B. WEALTHY - a wearable healthcare system: new frontier on e-textile. JTIT 2005;22:105-13.

36. Finni T, Hu M, Kettunen P, Vilavuo T, Cheng S. Measurement of EMG activity with textile electrodes embedded into clothing. Physiol Meas 2007;28:1405-19.

37. Pandian PS, Safeer KP, Gupta P, Shakunthala DT, Sundersheshu BS, Padaki VC. Wireless sensor network for wearable physiological monitoring. JNW 2008;3:21-9.

38. Kiourti A, Lee C, Volakis JL. Fabrication of textile antennas and circuits with 0.1 mm precision. Antennas Wirel Propag Lett 2016;15:151-3.

39. Tsolis A, Whittow W, Alexandridis A, Vardaxoglou J. Embroidery and related manufacturing techniques for wearable antennas: challenges and opportunities. Electronics 2014;3:314-38.

40. Castano LM, Flatau AB. Smart fabric sensors and e-textile technologies: a review. Smart Mater Struct 2014;23:053001.

41. Stoppa M, Chiolerio A. Wearable electronics and smart textiles: a critical review. Sensors 2014;14:11957-92.

42. Lin Z, Yang J, Li X, et al. Large-scale and washable smart textiles based on triboelectric nanogenerator arrays for self-powered sleeping monitoring. Adv Funct Mater 2018;28:1704112.

43. Jin H, Matsuhisa N, Lee S, Abbas M, Yokota T, Someya T. Enhancing the performance of stretchable conductors for e-textiles by controlled ink permeation. Adv Mater 2017;29:1605848.

44. Bai W, Zhai J, Zhou S, et al. Flexible smart wearable Co@C@carbon fabric for efficient electromagnetic shielding, thermal therapy, and human movement monitoring. Ind Eng Chem Res 2022;61:11825-39.

45. Fan W, He Q, Meng K et al. Machine-knitted washable sensor array textile for precise epidermal physiological signal monitoring. Sci Adv 2020;6:eaay2840.

46. Jeong S, Lee Y, Lee M, Song WJ, Park J, Sun J. Accelerated wound healing with an ionic patch assisted by a triboelectric nanogenerator. Nano Energy 2021;79:105463.

47. Wang L, Wang L, Zhang Y, et al. Weaving sensing fibers into electrochemical fabric for real-time health monitoring. Adv Funct Mater 2018;28:1804456.

48. Khozouie N, Malekhoseini R. Pregnancy healthcare monitoring system: a review. Smart Health 2024;31:100433.

49. Hu X, Chen Y, Wang X, et al. Wearable and regenerable electrochemical fabric sensing system based on molecularly imprinted polymers for real-time stress management. Adv Funct Mater 2024;34:2312897.

50. Liu L, Li J, Tian Z, et al. Self-powered porous polymer sensors with high sensitivity for machine learning-assisted motion and rehabilitation monitoring. Nano Energy 2024;128:109817.

51. Yang Y, Wei X, Zhang N, et al. A non-printed integrated-circuit textile for wireless theranostics. Nat Commun 2021;12:4876.

52. Peng Y, Dong J, Sun J, et al. Multimodal health monitoring via a hierarchical and ultrastretchable all-in-one electronic textile. Nano Energy 2023;110:108374.

53. Zhao Z, Yan C, Liu Z, et al. Machine-washable textile triboelectric nanogenerators for effective human respiratory monitoring through loom weaving of metallic yarns. Adv Mater 2016;28:10267-74.

54. Islam MR, Afroj S, Yin J, Novoselov KS, Chen J, Karim N. Advances in printed electronic textiles. Adv Sci 2024;11:e2304140.

55. Cesano F, Uddin MJ, Lozano K, Zanetti M, Scarano D. All-carbon conductors for electronic and electrical wiring applications. Front Mater 2020;7:219.

56. Dang C, Wang Z, Hughes-Riley T, et al. Fibres-threads of intelligence-enable a new generation of wearable systems. Chem Soc Rev 2024;53:8790-846.

57. Boumegnane A, Nadi A, Cherkaoui O, Tahiri M. Inkjet printing of silver conductive ink on textiles for wearable electronic applications. Mater Today Proc 2022;58:1235-41.

58. Smith AA, Li R, Xu L, Tse ZTH. A narrative review of in-textile sensors in human health applications. Adv Mater Technol 2024;9:2302141.

59. Jones CF, Resina L, Ferreira FC, Sanjuan-alberte P, Esteves T. Conductive core–shell nanoparticles: synthesis and applications. J Phys Chem C 2024;128:11083-100.

60. Wei S, Wang Q, Zhu J, Sun L, Lin H, Guo Z. Multifunctional composite core-shell nanoparticles. Nanoscale 2011;3:4474-502.

61. Ala O, Fan Q. Applications of conducting polymers in electronic textiles. Res J Text Apparel 2009;13:51-68.

62. Angelopoulos M. Conducting polymers in microelectronics. IBM J Res Dev 2001;45:57-75.

63. Lekpittaya P, Yanumet N, Grady BP, O’Rear EA. Resistivity of conductive polymer–coated fabric. J Appl Polym Sci 2004;92:2629-36.

64. Wallace GG, Campbell TE, Innis PC. Putting function into fashion: organic conducting polymer fibres and textiles. Fibers Polym 2007;8:135-42.

65. Kim HK, Kim MS, Chun SY, et al. Characteristics of electrically conducting polymer-coated textiles. Mol Cryst Liq Cryst 2003;405:161-9.

66. Seidel JM, Malmonge SM. Synthesis of polyHEMA hydrogels for using as biomaterials. Bulk and solution radical-initiated polymerization techniques. Mat Res 2000;3:79-83.

67. Shang J, Shao Z, Chen X. Electrical behavior of a natural polyelectrolyte hydrogel: chitosan/carboxymethylcellulose hydrogel. Biomacromolecules 2008;9:1208-13.

68. Guiseppi-Elie A. Electroconductive hydrogels: synthesis, characterization and biomedical applications. Biomaterials 2010;31:2701-16.

69. Frutiger A, Muth JT, Vogt DM, et al. Capacitive soft strain sensors via multicore-shell fiber printing. Adv Mater 2015;27:2440-6.

70. Agcayazi T, Chatterjee K, Bozkurt A, Ghosh TK. Flexible interconnects for electronic textiles. Adv Mater Technol 2018;3:1700277.

71. Mokhtar SMA, Alvarez de Eulate E, Yamada M, Prow TW, Evans DR. Conducting polymers in wearable devices. Med Devices Sens 2021;4:e10160.

72. Grancarić AM, Jerković I, Koncar V, et al. Conductive polymers for smart textile applications. J Ind Text 2018;48:612-42.

73. Chatterjee A, Deopura BL. Carbon nanotubes and nanofibre: an overview. Fibers Polym 2002;3:134-9.

74. Wang L. Functional nanofibre: enabling material for the next generation smart textiles. JFBI 2018;1:81-92.

75. Liu Y, Wang X, Qi K, Xin JH. Functionalization of cotton with carbon nanotubes. J Mater Chem 2008;18:3454.

76. Robinson JT, Perkins FK, Snow ES, Wei Z, Sheehan PE. Reduced graphene oxide molecular sensors. Nano Lett 2008;8:3137-40.

77. Chiu CW, Li JW, Huang CY, et al. Controlling the structures, flexibility, conductivity stability of three-dimensional conductive networks of silver nanoparticles/carbon-based nanomaterials with nanodispersion and their application in wearable electronic sensors. Nanomaterials 2020;10:1009.

78. Jiang L, Hong H, Hu J. Facile thermoplastic polyurethane-based multi-walled carbon nanotube ink for fabrication of screen-printed fabric electrodes of wearable e-textiles with high adhesion and resistance stability under large deformation. Text Res J 2021;91:2487-99.

79. Look D. Recent advances in ZnO materials and devices. Mater Sci Eng B 2001;80:383-7.

80. Özgür Ü, Alivov YI, Liu C, et al. A comprehensive review of ZnO materials and devices. J Appl Phys 2005;98:041301.

81. Mitzi DB. Templating and structural engineering in organic–inorganic perovskites. J Chem Soc Dalton Trans ;2001:1-12.

82. Li W, Wang Z, Deschler F, Gao S, Friend RH, Cheetham AK. Chemically diverse and multifunctional hybrid organic–inorganic perovskites. Nat Rev Mater 2017;2:BFnatrevmats201699.

83. Yang D, Westreich P, Frindt R. Transition metal dichalcogenide/polymer nanocomposites. Nanostruct Mater 1999;12:467-70.

84. Wang Y, Sarkar S, Yan H, Chhowalla M. Critical challenges in the development of electronics based on two-dimensional transition metal dichalcogenides. Nat Electron 2024;7:638-45.

85. Zheng Y, Yin R, Zhao Y, et al. Conductive MXene/cotton fabric based pressure sensor with both high sensitivity and wide sensing range for human motion detection and E-skin. Chem Eng J 2021;420:127720.

86. Silva N, Gonçalves LM, Carvalho H. Deposition of conductive materials on textile and polymeric flexible substrates. J Mater Sci Mater Electron 2013;24:635-43.

87. Kwon S, Kim H, Choi S, et al. Weavable and highly efficient organic light-emitting fibers for wearable electronics: a scalable, low-temperature process. Nano Lett 2018;18:347-56.

88. Hwang YH, Noh B, Lee J, Lee HS, Park Y, Choi KC. High-performance and reliable white organic light-emitting fibers for truly wearable textile displays. Adv Sci 2022;9:e2104855.

89. Zhao Y, Zhai Q, Dong D, et al. Highly stretchable and strain-insensitive fiber-based wearable electrochemical biosensor to monitor glucose in the sweat. Anal Chem 2019;91:6569-76.

90. Lee J, Kwon H, Seo J, et al. Conductive fiber-based ultrasensitive textile pressure sensor for wearable electronics. Adv Mater 2015;27:2433-9.

91. You X, He J, Nan N, et al. Stretchable capacitive fabric electronic skin woven by electrospun nanofiber coated yarns for detecting tactile and multimodal mechanical stimuli. J Mater Chem C 2018;6:12981-91.

92. Wu R, Ma L, Hou C, et al. Silk composite electronic textile sensor for high space precision 2D combo temperature-pressure sensing. Small 2019;15:e1901558.

93. Rotzler S, Schneider-ramelow M. Washability of E-textiles: failure modes and influences on washing reliability. Textiles 2021;1:37-54.

94. Li J, Zhang X, Ding Y, et al. Multifunctional carbon fiber@NiCo/polyimide films with outstanding electromagnetic interference shielding performance. Chem Eng J 2022;427:131937.

95. Cheng Y, Zhu M, Chi M, et al. MXene/TPU hybrid fabrics enable smart wound management and thermoresponsive drug delivery. ACS Appl Mater Interfaces 2024;16:20105-18.

96. Chiu C, Lin C, Hong P. Melt-spinning and thermal stability behavior of TiO2 nanoparticle/polypropylene nanocomposite fibers. J Polym Res 2011;18:367-72.

97. Alagirusamy R, Fangueiro R, Ogale V, Padaki N. Hybrid yarns and textile preforming for thermoplastic composites. Text Prog 2006;38:1-71.

98. Horan RL, Collette AL, Lee C, Antle K, Chen J, Altman GH. Yarn design for functional tissue engineering. J Biomech 2006;39:2232-40.

99. Shaker K, Umair M, Ashraf W, Nawab Y. Fabric manufacturing. Phys Sci Rev 2016;1:20160024.

100. Selbmann R, Gibmeier J, Simon N, Kräusel V, Bergmann M. Residual stress engineering for wire drawing of austenitic stainless steel X5CrNi18-10 by variation in die geometries - effect of drawing speed and process temperature. Materials 2024;17:1174.

101. Bhuyan P, Singh M, Wei Y, et al. Thread-analogous elastic fibers with liquid metal core by drawing at room temperature for multifunctional smart textiles. Chem Eng J 2024;480:147944.

102. Ramamoorthy SK, Skrifvars M, Persson A. A review of natural fibers used in biocomposites: plant, animal and regenerated cellulose fibers. Polym Rev 2015;55:107-62.

103. Akter T, Hossain MS. Application of plant fibers in environmental friendly composites for developed properties: a review. Clean Mater 2021;2:100032.

104. Cheng H, Dowd MK, Selling G, Biswas A. Synthesis of cellulose acetate from cotton byproducts. Carbohydr Polym 2010;80:449-52.

105. Zhang S, Chen XW, Li YL, Du WP. Study on the thermal properties of high-strength flame resistant vinylon blending fabric. AMR 2012;627:105-9.

106. Morton W. The arrangement of fibers in single yarns. Text Res J 1956;26:325-31.

107. Hwang B, Lund A, Tian Y, Darabi S, Müller C. Machine-washable conductive silk yarns with a composite coating of Ag nanowires and PEDOT:PSS. ACS Appl Mater Interfaces 2020;12:27537-44.

108. Havigh R, Mahmoudi Chenari H. A comprehensive study on the effect of carbonization temperature on the physical and chemical properties of carbon fibers. Sci Rep 2022;12:10704.

109. Bengtsson A, Hecht P, Sommertune J, Ek M, Sedin M, Sjöholm E. Carbon fibers from lignin–cellulose precursors: effect of carbonization conditions. ACS Sustain Chem Eng 2020;8:6826-33.

110. Gupta A, Dhakate SR, Pal P, Dey A, Iyer PK, Singh DK. Effect of graphitization temperature on structure and electrical conductivity of poly-acrylonitrile based carbon fibers. Diam Relat Mater 2017;78:31-8.

111. Pourian Azar G, Fox D, Fedutik Y, Krishnan L, Cobley AJ. Functionalised copper nanoparticle catalysts for electroless copper plating on textiles. Surf Coat Technol 2020;396:125971.

112. Moazzenchi B, Montazer M. Click electroless plating of nickel nanoparticles on polyester fabric: electrical conductivity, magnetic and EMI shielding properties. Colloid Surfacs A 2019;571:110-24.

113. Zuo R, Chen J, Han Z, Dong Y, Jow J. Electroless silver plating on modified fly ash particle surface. Appl Surf Sci 2020;513:145857.

114. Hussain N, Yousif M, Mehdi M, et al. Electroless deposition: a superficial route to synthesis of highly conductive electrospun nylon 6 nanofibers. Fibers Polym 2022;23:680-9.

115. Qi Q, Wang Y, Ding X, Wang W, Xu R, Yu D. High-electromagnetic-shielding cotton fabric prepared using multiwall carbon nanotubes/nickel–phosphorus electroless plating. Appl Organomet Chem 2020;34:e5434.

116. Hannula P, Peltonen A, Aromaa J, et al. Carbon nanotube-copper composites by electrodeposition on carbon nanotube fibers. Carbon 2016;107:281-7.

117. Mei X, Lu L, Xie Y, Yu YX, Tang Y, Teh KS. Preparation of flexible carbon fiber fabrics with adjustable surface wettability for high-efficiency electromagnetic interference shielding. ACS Appl Mater Interfaces 2020;12:49030-41.

118. Malureanu R, Zalkovskij M, Andryieuski A, Lavrinenko AV. Controlled Ag electroless deposition in bulk structures with complex three-dimensional profiles. J Electrochem Soc 2010;157:K284.

119. Gill TM, Zhao J, Berenschot EJW, Tas N, Zheng X. Conformal electroless nickel plating on silicon wafers, convex and concave pyramids, and ultralong nanowires. ACS Appl Mater Interfaces 2018;10:22834-40.

120. Bahadormanesh B, Ghorbani M, Kordkolaei NL. Electrodeposition of nanocrystalline Zn/Ni multilayer coatings from single bath: Influences of deposition current densities and number of layers on characteristics of deposits. Appl Surf Sci 2017;404:101-9.

121. Illy BN, Cruickshank AC, Schumann S, et al. Electrodeposition of ZnO layers for photovoltaic applications: controlling film thickness and orientation. J Mater Chem 2011;21:12949.

122. Preda N, Costas A, Lilli M, et al. Functionalization of basalt fibers with ZnO nanostructures by electroless deposition for improving the interfacial adhesion of basalt fibers/epoxy resin composites. Compos Part A Appl S 2021;149:106488.

123. Liu C, Li X, Li X, et al. Preparation of conductive polyester fibers using continuous two-step plating silver. Materials 2018;11:2033.

124. Yan W, Dong C, Xiang Y, et al. Thermally drawn advanced functional fibers: new frontier of flexible electronics. Mater Today 2020;35:168-94.

125. Loke G, Yan W, Khudiyev T, Noel G, Fink Y. Recent progress and perspectives of thermally drawn multimaterial fiber electronics. Adv Mater 2020;32:e1904911.

126. Tao G, Stolyarov AM, Abouraddy AF. Multimaterial fibers. Int J Appl Glass Sci 2012;3:349-68.

127. Gumennik A, Stolyarov AM, Schell BR, et al. All-in-fiber chemical sensing. Adv Mater 2012;24:6005-9.

128. Orf ND, Shapira O, Sorin F, et al. Fiber draw synthesis. Proc Natl Acad Sci U S A 2011;108:4743-7.

129. Hufenus R, Yan Y, Dauner M, Kikutani T. Melt-spun fibers for textile applications. Materials 2020;13:4298.

130. Ryu S, Lee P, Chou JB, et al. Extremely elastic wearable carbon nanotube fiber strain sensor for monitoring of human motion. ACS Nano 2015;9:5929-36.

131. Cheng Y, Wang R, Sun J, Gao L. A stretchable and highly sensitive graphene-based fiber for sensing tensile strain, bending, and torsion. Adv Mater 2015;27:7365-71.

132. Probst H, Katzer K, Nocke A, Hickmann R, Zimmermann M, Cherif C. Melt spinning of highly stretchable, electrically conductive filament yarns. Polymers 2021;13:590.

133. Mirabedini A, Foroughi J, Wallace GG. Developments in conducting polymer fibres: from established spinning methods toward advanced applications. RSC Adv 2016;6:44687-716.

134. Zhao Y, Dong D, Gong S, et al. A moss-inspired electroless gold-coating strategy toward stretchable fiber conductors by dry spinning. Adv Elect Mater 2019;5:1800462.

135. Biswas MC, Bush B, Ford E. Glucaric acid additives for the antiplasticization of fibers wet spun from cellulose acetate/acetic acid/water. Carbohydr Polym 2020;245:116510.

136. Fahma F, Febiyanti I, Lisdayana N, et al. Production of polyvinyl alcohol–alginate–nanocellulose fibers. Starch Stärke 2022;74:2100032.

137. Zhou G, Byun JH, Oh Y, et al. Highly sensitive wearable textile-based humidity sensor made of high-strength, single-walled carbon nanotube/poly(vinyl alcohol) filaments. ACS Appl Mater Interfaces 2017;9:4788-97.

138. Ma R, Lee J, Choi D, Moon H, Baik S. Knitted fabrics made from highly conductive stretchable fibers. Nano Lett 2014;14:1944-51.

139. Vigolo B, Pénicaud A, Coulon C, et al. Macroscopic fibers and ribbons of oriented carbon nanotubes. Science 2000;290:1331-4.

140. Eom W, Shin H, Ambade RB, et al. Large-scale wet-spinning of highly electroconductive MXene fibers. Nat Commun 2020;11:2825.

141. León-Boigues L, Flores A, Gómez-Fatou MA, Vega JF, Ellis GJ, Salavagione HJ. PET/graphene nanocomposite fibers obtained by dry-jet wet-spinning for conductive textiles. Polymers 2023;15:1245.

142. Shang L, Yu Y, Liu Y, Chen Z, Kong T, Zhao Y. Spinning and applications of bioinspired fiber systems. ACS Nano 2019;13:2749-72.

143. Busolo T, Szewczyk PK, Nair M, Stachewicz U, Kar-Narayan S. Triboelectric yarns with electrospun functional polymer coatings for highly durable and washable smart textile applications. ACS Appl Mater Interfaces 2021;13:16876-86.

144. Tang Z, Jia S, Wang F, et al. Highly stretchable core-sheath fibers via wet-spinning for wearable strain sensors. ACS Appl Mater Interfaces 2018;10:6624-35.

145. Lu Y, Xiao X, Fu J, et al. Novel smart textile with phase change materials encapsulated core-sheath structure fabricated by coaxial electrospinning. Chem Eng J 2019;355:532-9.

146. Gao T, Yang Z, Chen C, et al. Three-dimensional printed thermal regulation textiles. ACS Nano 2017;11:11513-20.

147. Chen Y, Deng Z, Ouyang R, et al. 3D printed stretchable smart fibers and textiles for self-powered e-skin. Nano Energy 2021;84:105866.

148. Guo SZ, Qiu K, Meng F, Park SH, McAlpine MC. 3D printed stretchable tactile sensors. Adv Mater 2017;29:1701218.

149. Quan Z, Larimore Z, Wu A, et al. Microstructural design and additive manufacturing and characterization of 3D orthogonal short carbon fiber/acrylonitrile-butadiene-styrene preform and composite. Compos Sci Technol 2016;126:139-48.

150. Kwak SS, Yoon H, Kim S. Textile-based triboelectric nanogenerators for self-powered wearable electronics. Adv Funct Mater 2019;29:1804533.

151. Hallal A, Younes R, Fardoun F. Review and comparative study of analytical modeling for the elastic properties of textile composites. Compos Part B Eng 2013;50:22-31.

152. Zhao Z, Huang Q, Yan C, et al. Machine-washable and breathable pressure sensors based on triboelectric nanogenerators enabled by textile technologies. Nano Energy 2020;70:104528.

153. Dong K, Peng X, An J, et al. Shape adaptable and highly resilient 3D braided triboelectric nanogenerators as e-textiles for power and sensing. Nat Commun 2020;11:2868.

154. Hamedi M, Forchheimer R, Inganäs O. Towards woven logic from organic electronic fibres. Nat Mater 2007;6:357-62.

155. Buechley L, Eisenberg M. Fabric PCBs, electronic sequins, and socket buttons: techniques for e-textile craft. Pers Ubiquit Comput 2009;13:133-50.

157. Gokarneshan N. Fabric structure and design. New Delhi: New Age International; 2004. pp. 7-45. Available from: https://books.google.com/books?hl=zh-CN&lr=&id=VQGx5ZyFm2AC&oi=fnd&pg=PA1&dq=Fabric+structure+and+design.&ots=PCyQ44h1jH&sig=HlA2xr0-yQef2qfC5iagT9n_5Qo#v=onepage&q=Fabric%20structure%20and%20design.&f=false. [Last accessed on 25 Nov 2024].

158. Kim G, Vu CC, Kim J. Single-layer pressure textile sensors with woven conductive yarn circuit. Appl Sci 2020;10:2877.

159. Chen J, He T, Du Z, Lee C. Review of textile-based wearable electronics: from the structure of the multi-level hierarchy textiles. Nano Energy 2023;117:108898.

160. Pu J, Ma K, Luo Y, et al. Textile electronics for wearable applications. Int J Extrem Manuf 2023;5:042007.

161. Cheng KB, Ramakrishna S, Lee KC. Electrostatic discharge properties of knitted copper wire/glass fiber fabric reinforced polypropylene composites. Polym Composite 2001;22:185-96.

162. Zhang H, Tao X, Yu T, Wang S. Conductive knitted fabric as large-strain gauge under high temperature. Sensor Actuat A Phys 2006;126:129-40.

163. Katragadda RB, Xu Y. A novel intelligent textile technology based on silicon flexible skins. Sensor Actuat A Phys 2008;143:169-74.

164. He Y, Mei M, Yang X, Wei K, Qu Z, Fang D. Experimental characterization of the compaction behavior in preforming process for 3D stitched carbon fabric. Compos Commun 2020;19:203-9.

165. Wan Y, Huang Y, He F, Li Q, Lian J. Tribological properties of three-dimensional braided carbon/Kevlar/epoxy hybrid composites under dry and lubricated conditions. Mater Sci Eng A 2007;452-3:202-9.

166. Yang S, Macharia DK, Ahmed S, et al. Flexible and reusable non-woven fabric photodetector based on polypyrrole/crystal violate lactone for NIR light detection and writing. Adv Fiber Mater 2020;2:150-60.

167. Kang TH, Merritt CR, Grant E, Pourdeyhimi B, Nagle HT. Nonwoven fabric active electrodes for biopotential measurement during normal daily activity. IEEE Trans Biomed Eng 2008;55:188-95.

168. Zhou Y, He J, Wang H, et al. Highly sensitive, self-powered and wearable electronic skin based on pressure-sensitive nanofiber woven fabric sensor. Sci Rep 2017;7:12949.

169. Mi H, Zhong L, Tang X, et al. Electroluminescent fabric woven by ultrastretchable fibers for arbitrarily controllable pattern display. ACS Appl Mater Interfaces 2021;13:11260-7.

170. Sun C, Li X, Cai Z, Ge F. Carbonized cotton fabric in-situ electrodeposition polypyrrole as high-performance flexible electrode for wearable supercapacitor. Electrochim Acta 2019;296:617-26.

171. Ali I, Islam MR, Yin J, et al. Advances in smart photovoltaic textiles. ACS Nano 2024;18:3871-915.

172. Jan AA, Kim S, Kim S. A skin-wearable and self-powered laminated pressure sensor based on triboelectric nanogenerator for monitoring human motion. Soft Sci 2024;4:10.

173. Liu J, Tian G, Yang W, Deng W. Recent progress in flexible piezoelectric devices toward human-machine interactions. Soft Sci 2022;2:22.

174. Kim N, Lee JM, Moradnia M, et al. Biocompatible composite thin-film wearable piezoelectric pressure sensor for monitoring of physiological and muscle motions. Soft Sci 2022;2:8.

175. Jiang W, Li T, Hussain B, et al. Facile fabrication of cotton-based thermoelectric yarns for the construction of textile generator with high performance in human heat harvesting. Adv Fiber Mater 2023;5:1725-36.

176. Li M, Li Z, Ye X, Zhang X, Qu L, Tian M. Tendril-inspired 900% ultrastretching fiber-based Zn-ion batteries for wearable energy textiles. ACS Appl Mater Interfaces 2021;13:17110-7.

177. Liu M, Zhang Y, Ou L, et al. A stretchable tactile sensor based on ALD-prepared conductive composite textile. Appl Mater Today 2024;37:102099.

178. Kovalska E, Lam HT, Saadi Z, et al. Textile beeswax triboelectric nanogenerator as self-powered sound detectors and mechano-acoustic energy harvesters. Nano Energy 2024;120:109109.

179. Zhao X, Liu Z, Sun Z, Zhang Y, Han T. Fabricating a photochromic Schiff base into a wearable cellulose sensor and a smart textile for ultraviolet radiation monitoring outdoors. Mater Lett 2024;364:136382.

180. Zhao P, Song Y, Xie P, et al. All-organic smart textile sensor for deep-learning-assisted multimodal sensing. Adv Funct Mater 2023;33:2301816.

181. He X, Yang S, Pei Q, et al. Integrated smart janus textile bands for self-pumping sweat sampling and analysis. ACS Sens 2020;5:1548-54.

182. Chen C, Xie G, Dai J, et al. Integrated core-shell structured smart textiles for active NO2 concentration and pressure monitoring. Nano Energy 2023;116:108788.

183. Golparvar AJ, Yapici MK. Graphene smart textile-based wearable eye movement sensor for electro-ocular control and interaction with objects. J Electrochem Soc 2019;166:B3184-93.

184. Mattana G, Kinkeldei T, Leuenberger D, et al. Woven temperature and humidity sensors on flexible plastic substrates for E-textile applications. IEEE Sensors J 2013;13:3901-9.

185. Li Z, Hansen K, Yao Y, Ma Y, Moon K, Wong CP. The conduction development mechanism of silicone-based electrically conductive adhesives. J Mater Chem C 2013;1:4368.

186. Ding Y, Jiang J, Wu Y, et al. Porous conductive textiles for wearable electronics. Chem Rev 2024;124:1535-648.

187. Wei C, Cheng R, Ning C, et al. A self-powered body motion sensing network integrated with multiple triboelectric fabrics for biometric gait recognition and auxiliary rehabilitation training. Adv Funct Mater 2023;33:2303562.

188. Vu CC, Kim J. Human motion recognition by textile sensors based on machine learning algorithms. Sensors 2018;18:3109.

189. Ejupi A, Menon C. Detection of talking in respiratory signals: a feasibility study using machine learning and wearable textile-based sensors. Sensors 2018;18:2474.

190. Zhu J, Cho M, Li Y, et al. Machine learning-enabled textile-based graphene gas sensing with energy harvesting-assisted IoT application. Nano Energy 2021;86:106035.

191. Jiang Y, An J, Liang F, et al. Knitted self-powered sensing textiles for machine learning-assisted sitting posture monitoring and correction. Nano Res 2022;15:8389-97.

192. Fang Y, Zou Y, Xu J, et al. Ambulatory cardiovascular monitoring via a machine-learning-assisted textile triboelectric sensor. Adv Mater 2021;33:e2104178.

193. Zhao P, Song Y, Hu Z, et al. Artificial intelligence enabled biodegradable all-textile sensor for smart monitoring and recognition. Nano Energy 2024;130:110118.

194. Avellar L, Stefano Filho C, Delgado G, Frizera A, Rocon E, Leal-Junior A. AI-enabled photonic smart garment for movement analysis. Sci Rep 2022;12:4067.

195. Xiong Y, Luo L, Yang J, et al. Scalable spinning, winding, and knitting graphene textile TENG for energy harvesting and human motion recognition. Nano Energy 2023;107:108137.

196. Ali SM, Sovuthy C, Imran MA, Socheatra S, Abbasi QH, Abidin ZZ. Recent advances of wearable antennas in materials, fabrication methods, designs, and their applications: state-of-the-art. Micromachines 2020;11:888.

197. Tsolis A, Bakogianni S, Angelaki C, Alexandridis AA. A review of clothing components in the development of wearable textile antennas: design and experimental procedure. Sensors 2023;23:3289.

198. Wang Z, Liu Y, Zhou Z, Chen P, Peng H. Towards integrated textile display systems. Nat Rev Electr Eng 2024;1:466-77.

199. Choi S, Jo W, Jeon Y, et al. Multi-directionally wrinkle-able textile OLEDs for clothing-type displays. npj Flex Electron 2020;4:96.

200. Song H, Song YJ, Hong J, et al. Water stable and matrix addressable OLED fiber textiles for wearable displays with large emission area. npj Flex Electron 2022;6:199.

201. Shi X, Zuo Y, Zhai P, et al. Large-area display textiles integrated with functional systems. Nature 2021;591:240-5.

202. Chen C, Feng J, Li J, Guo Y, Shi X, Peng H. Functional fiber materials to smart fiber devices. Chem Rev 2023;123:613-62.

203. Zhang J, Zhang Y, Li Y, Wang P. Textile-based flexible pressure sensors: a review. Polym Rev 2022;62:65-94.

204. Ouyang Z, Li S, Liu J, et al. Bottom-up reconstruction of smart textiles with hierarchical structures to assemble versatile wearable devices for multiple signals monitoring. Nano Energy 2022;104:107963.

205. Hu X, Huang T, Liu Z, et al. Conductive graphene-based E-textile for highly sensitive, breathable, and water-resistant multimodal gesture-distinguishable sensors. J Mater Chem A 2020;8:14778-87.

206. Sheng F, Yi J, Shen S, et al. Self-powered smart arm training band sensor based on extremely stretchable hydrogel conductors. ACS Appl Mater Interfaces 2021;13:44868-77.

207. Li Y, Yin J, Liu S, et al. Learning hand kinematics for Parkinson’s disease assessment using a multimodal sensor glove. Adv Sci 2023;10:e2206982.

208. Lin R, Kim HJ, Achavananthadith S, et al. Wireless battery-free body sensor networks using near-field-enabled clothing. Nat Commun 2020;11:444.

209. Zhang Y, Zhou Z, Fan Z, et al. Self-powered multifunctional transient bioelectronics. Small 2018;14:e1802050.

210. Lin R, Fan Y, Xie Y, et al. A self-powered wearable seizure-monitoring/brain-stimulating system for potential epilepsy treatment. Nano Energy 2023;107:108121.

211. Li BM, Reese BL, Ingram K, et al. Textile-integrated liquid metal electrodes for electrophysiological monitoring. Adv Healthc Mater 2022;11:e2200745.

212. Promphet N, Hinestroza JP, Rattanawaleedirojn P, et al. Cotton thread-based wearable sensor for non-invasive simultaneous diagnosis of diabetes and kidney failure. Sensor Actuat B Chem 2020;321:128549.

213. Takeshita T, Yoshida M, Takei Y, et al. Relationship between contact pressure and motion artifacts in ECG measurement with electrostatic flocked electrodes fabricated on textile. Sci Rep 2019;9:5897.

214. Wang L, Pan Y, He D, et al. Conductive polyester fabrics with high washability as electrocardiogram textile electrodes. ACS Appl Polym Mater 2022;4:1440-7.

215. Tu H, Li X, Lin X, Lang C, Gao Y. Washable and flexible screen-printed Ag/AgCl electrode on textiles for ECG monitoring. Polymers 2023;15:3665.

216. Zhao J, Deng J, Liang W, et al. Water-retentive, 3D knitted textile electrode for long-term and motion state bioelectrical signal acquisition. Compos Sci Technol 2022;227:109606.

217. Dore H, Aviles-Espinosa R, Luo Z, Anton O, Rabe H, Rendon-Morales E. Characterisation of textile embedded electrodes for use in a neonatal smart mattress electrocardiography system. Sensors 2021;21:999.

218. Ozturk O, Yapici MK. Surface Electromyography with wearable graphene textiles. IEEE Sensors J 2021;21:14397-406.

219. Spanu A, Botter A, Zedda A, Cerone GL, Bonfiglio A, Pani D. Dynamic surface electromyography using stretchable screen-printed textile electrodes. IEEE Trans Neural Syst Rehabil Eng 2021;29:1661-8.

220. Carneiro MR, de Almeida AT, Tavakoli M. Wearable and comfortable e-textile headband for long-term acquisition of forehead EEG signals. IEEE Sensors J 2020;20:15107-16.

221. Tseghai GB, Malengier B, Fante KA, Van Langenhove L. Hook fabric electroencephalography electrode for brain activity measurement without shaving the head. Polymers 2023;15:3673.

222. Toral V, Castillo E, Albretch A, et al. Cost-effective printed electrodes based on emerging materials applied to biosignal acquisition. IEEE Access 2020;8:127789-800.

223. Rusanen M, Huttunen R, Korkalainen H, et al. Generalizable deep learning-based sleep staging approach for ambulatory textile electrode headband recordings. IEEE J Biomed Health Inform 2023;27:1869-80.

224. Loke G, Khudiyev T, Wang B, et al. Digital electronics in fibres enable fabric-based machine-learning inference. Nat Commun 2021;12:3317.

225. Fan W, Liu T, Wu F, et al. An antisweat interference and highly sensitive temperature sensor based on poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) fiber coated with polyurethane/graphene for real-time monitoring of body temperature. ACS Nano 2023;17:21073-82.

226. Li W, Song Z, Kong H, et al. An integrated wearable self-powered platform for real-time and continuous temperature monitoring. Nano Energy 2022;104:107935.

227. Ma L, Wu R, Patil A, et al. Full-textile wireless flexible humidity sensor for human physiological monitoring. Adv Funct Mater 2019;29:1904549.

228. Ali S, Khan S, Khan A, Bermak A. Developing conductive fabric threads for human respiratory rate monitoring. IEEE Sensors J 2021;21:4350-6.

229. Takamatsu S, Lonjaret T, Crisp D, Badier JM, Malliaras GG, Ismailova E. Direct patterning of organic conductors on knitted textiles for long-term electrocardiography. Sci Rep 2015;5:15003.

230. Kim H, Rho S, Lim D, Jeong W. Characterization of embroidered textile-based electrode for EMG smart wear according to stitch technique. Fash Text 2023;10:351.

231. Tseghai GB, Malengier B, Fante KA, Van Langenhove L. Dry electroencephalography textrode for brain activity monitoring. IEEE Sensors J 2021;21:22077-85.

232. Ha H, Suryaprabha T, Choi C, et al. Recent research trends in textile-based temperature sensors: a mini review. Nanotechnology 2023;34:422001.

233. Zhang X, Tang S, Ma R, et al. High-performance multimodal smart textile for artificial sensation and health monitoring. Nano Energy 2022;103:107778.

234. Nicolò A, Massaroni C, Schena E, Sacchetti M. The importance of respiratory rate monitoring: from healthcare to sport and exercise. Sensors 2020;20:6396.

235. Feng Z, He Q, Qiu J, et al. Iontronic textile-based capacitive pressure sensor for unconstrained respiration and heartbeat monitoring. Adv Mater Technol 2023;8:2300949.

236. Lin Z, Nie S, He Q, et al. Wearable and flexible helical pressure sensor for noninvasive respiratory monitoring. ACS Appl Eng Mater 2023;1:2765-71.

237. Khan A, Haque MN, Kabiraz DC, et al. A review on advanced nanocomposites materials based smart textile biosensor for healthcare monitoring from human sweat. Sensor Actuat A Phys 2023;350:114093.

238. Liu L, Ahn JH, Wang B. Wearable plasmonic biofluid sensors as your photonic skin. Soft Sci 2023;3:6.

239. Brasier N, Niederberger C, Salvatore GA. The sweat rate as a digital biomarker in clinical medicine beyond sports science. Soft Sci 2024;4:6.

240. Zhao G, Li Z, Huang X, Zhang Q, Liu Y, Yu X. Recent advances of sweat sampling, sensing, energy-harvesting and data-display toward flexible sweat electronics. Soft Sci 2024;4:18.

241. Li X, Dai B, Wang L, Yang X, Xu T, Zhang X. Radiative cooling and anisotropic wettability in E-textile for comfortable biofluid monitoring. Biosens Bioelectron 2023;237:115434.

242. Peng J, Cheng H, Liu J, et al. Superhydrophobic MXene-based fabric with electromagnetic interference shielding and thermal management ability for flexible sensors. Adv Fiber Mater 2023;5:2099-113.

243. Zhou Z, Padgett S, Cai Z, et al. Single-layered ultra-soft washable smart textiles for all-around ballistocardiograph, respiration, and posture monitoring during sleep. Biosens Bioelectron 2020;155:112064.

244. Bing Y, Xue H, Li F, Zhao H, Lin X, Zhang T. Real-time sleep apnea monitoring system enabled by high-performance strain sensors based on elastic E-fibers. IEEE Sensors J 2024;24:19756-62.

245. Hwang S, Kang M, Lee A, et al. Integration of multiple electronic components on a microfibre towards an emerging electronic textile platform. Nat Commun 2022;13:3173.

246. Yang W, Lin S, Gong W, et al. Single body-coupled fiber enables chipless textile electronics. Science 2024;384:74-81.

247. Wang P, Ma X, Lin Z, et al. Well-defined in-textile photolithography towards permeable textile electronics. Nat Commun 2024;15:887.

248. Hoofnagle CJ, van der Sloot B, Borgesius FZ. The European Union general data protection regulation: what it is and what it means. Inf Commun Technol L 2019;28:65-98.

249. Bhutani P, Joshi G, Raja N, et al. U.S. FDA approved drugs from 2015-June 2020: a perspective. J Med Chem 2021;64:2339-81.

Cite This Article

Review Article
Open Access
Textile electronics for ubiquitous health monitoring
Feng-Chang Huang, ... Li-Jia Pan

How to Cite

Huang, F. C.; Sun, X. D.; Shi, Y.; Pan, L. J. Textile electronics for ubiquitous health monitoring. Soft Sci. 2024, 4, 40. http://dx.doi.org/10.20517/ss.2024.37

Download Citation

If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click on download.

Export Citation File:

Type of Import

Tips on Downloading Citation

This feature enables you to download the bibliographic information (also called citation data, header data, or metadata) for the articles on our site.

Citation Manager File Format

Use the radio buttons to choose how to format the bibliographic data you're harvesting. Several citation manager formats are available, including EndNote and BibTex.

Type of Import

If you have citation management software installed on your computer your Web browser should be able to import metadata directly into your reference database.

Direct Import: When the Direct Import option is selected (the default state), a dialogue box will give you the option to Save or Open the downloaded citation data. Choosing Open will either launch your citation manager or give you a choice of applications with which to use the metadata. The Save option saves the file locally for later use.

Indirect Import: When the Indirect Import option is selected, the metadata is displayed and may be copied and pasted as needed.

About This Article

Special Issue

This article belongs to the Special Issue Smart Fibers and Electronic Textiles
© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, sharing, adaptation, distribution and reproduction in any medium or format, for any purpose, even commercially, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Data & Comments

Data

Views
114
Downloads
19
Citations
0
Comments
0
0

Comments

Comments must be written in English. Spam, offensive content, impersonation, and private information will not be permitted. If any comment is reported and identified as inappropriate content by OAE staff, the comment will be removed without notice. If you have any queries or need any help, please contact us at support@oaepublish.com.

0
Download PDF
Share This Article
Scan the QR code for reading!
See Updates
Contents
Figures
Related
Soft Science
ISSN 2769-5441 (Online)
Follow Us

Portico

All published articles are preserved here permanently:

https://www.portico.org/publishers/oae/

Portico

All published articles are preserved here permanently:

https://www.portico.org/publishers/oae/