Nanogenerators in Biomedical Frontiers: Revolutionizing Self-Powered Healthcare Systems.

Self-powered systems have emerged as transformative technologies that address the growing demand for sustainable, autonomous, and miniaturized energy solutions for next-generation biomedical devices. Unlike conventional sensors and therapeutic platforms that rely on external power sources or batteries, self-powered nanogeneratorsbased on piezoelectric, triboelectric, and hybrid nanogeneratorscan harvest biomechanical or environmental energy to enable continuous operation. This review highlights the basics of nanogenerator mechanisms and material innovations, extending to their strategic integration into advanced biomedical applications. Particular emphasis is placed on applications such as regenerative hair growth techniques using electrical stimulation, motion-triggered drug release patches that ensure precise and sustained delivery, biocompatible electronic skin (E-skin) for real-time physiological sensing, wearable devices for continuous health monitoring, sweat-resistant wearables, hearing aids, ligament strain and bladder sensors, respiration-driven monitors, smart eye sensors, and scaffolds for cardiovascular and bone tissue repair through bioelectric cues. By evaluating both the opportunities and challenges, including energy conversion efficiency, long-term biocompatibility, device stability, and large-scale fabrication, this review provides a balanced outlook on the future of self-powered biomedical systems. The insights presented herein not only underscore their clinical and technological relevance but also identify key research directions required to bridge the gap between laboratory prototypes and practical healthcare applications.