Promoting maturation and contractile function of neonatal rat cardiomyocytes by self-powered implantable triboelectric nanogenerator

Cardiomyocyte-based therapeutic strategy is a promising approach to treat myocardial injury; however, the prognostic power of this approach is currently limited by the immaturity of cardiomyocytes. Here, a flexible self-powered implantable electrical stimulator based on the triboelectric nanogenerator (TENG) was proposed to induce the maturation of cardiomyocytes by generating an electric field on the interdigitated electrode. The results showed that the TENG-based self-powered stimulator significantly promoted the maturation of neonatal rat cardiomyocytes (NRCMs) in vitro by increasing the expression of connexin 43, α-actinin, and c-troponin T. In addition, electrical stimulation also improved sarcomere organization and fracture formation, and significantly increased the intracellular Ca2+ levels, Ca2+ transient rate, and Ca2+ peak amplitudes of cardiomyocytes. TENG was also shown to be driven by the breath of rats and the heartbeat of rabbits, suggesting it could be used as an implantable medical electronic device for electrically promoting the maturation of neonatal cardiomyocytes. This work develops a TENG-based self-powered implantable medical device, which provides important technical support for clinical treatment of myocardial defects and restoration of the physiological function of cardiac tissue.