Flexible Stretchable Piezoelectric Films for Tissue Repair and Health Detection.

In the context of deepening interdisciplinary research and increasing public health awareness, self-powered technology based on piezoelectric materials has gradually attracted attention in the field of health monitoring and treatment owing to its wireless and passive nature. Sustainable development has prompted the development of degradable piezoelectric materials. However, most degradable piezoelectric materials cannot be applied to active parts of the human body because of their poor strain capacity and toughness. In this study, based on poly (L-lactic acid) (PLLA) and recombinant human type I collagen (Col I), a biodegradable, stretchable d-PLLA/Col piezoelectric film is prepared using electrospinning technology. Cross-linked Col I provides d-PLLA/Col with better flexibility and stretchability, which can adapt to low-frequency tissue deformation or activity, thus improving fit stability and electromechanical sensing performance in wearable applications. Furthermore, under a high-frequency ultrasonic drive, electrical stimulation generated by d-PLLA/Col synergistically promotes wound healing in rats with a biomimetic extracellular matrix and structure. This study provides new insights into the development of degradable piezoelectric materials and offers a feasible strategy for next-generation health diagnostic and treatment devices.