Piezoelectric interfaces pioneering autonomous and personalized diagnostics

Piezoelectric interfaces are emerging as powerful tools for autonomous and personalized biomedical diagnostics by enabling real-time sensing and energy harvesting from physiological activities. Among them, piezoelectric nanogenerators (PENG) exemplify the integration of mechanical-to-electrical transduction with wearable and implantable applications, supporting self-powered operation without external power supplies. This review summarizes the fundamental principles of piezoelectricity and the development of representative materials, including inorganic ceramics, organic polymers, and hybrid composites, all tailored for biomedical use. Advances in fabrication strategies such as nanoscale patterning, multilayer assembly, and additive manufacturing have enhanced the flexibility, sensitivity, and biocompatibility of PENG-based systems. These devices have shown significant promise in applications such as cardiovascular and respiratory monitoring, neuromuscular sensing, and wound healing, where continuous and accurate physiological tracking is essential. Despite these advances, challenges remain in improving energy conversion efficiency under low-frequency biological motions, ensuring stable long-term biocompatibility, and integrating energy harvesting with storage and signal processing. Future directions include the incorporation of artificial intelligence for intelligent data analysis and the adoption of sustainable materials to enable next-generation diagnostic tools that are autonomous, eco-friendly, and suitable for precision medicine.