fig5

Figure 5. Representative architectures and working principles of piezoelectric biosensors. (A) Schematic of a wearable cardiac ultrasound imager based on stretchable piezoelectric transducer arrays for real-time heart monitoring. Reproduced with permission^[111]. Copyright 2023, Springer; (B) Configuration of a SAW biosensor for E. coil detection, illustrating antibody immobilization on the delay line and bacterial capture. Reproduced with permission^[112]. Copyright 2024, Royal Society of Chemistry; (C) Real-time monitoring of S. aureus lysis on a QCM sensor, showing the experimental setup for tracking mass and dissipation changes during phage/enzyme treatment. Reproduced with permission^[114]. Copyright 2025, Springer. IDT: Interdigital transducer; E. coli: Escherichia coli; S. aureus: Staphylococcus aureus; QCM: quartz crystal microbalance.