Piezoelectric nanocomposite patch for self-powered bioelectrical stimulation for cardiac tissue engineering

Cardiovascular diseases remain the leading cause of mortality worldwide, and myocardial infarction results in irreversible loss of functional myocardium with limited regenerative treatment options. Here, we report a self-responsive piezoelectric elastomeric patch designed for cardiac tissue engineering (CTE) by integrating dual nanofillers (TiC and MoS₂; 2 phr each) into a polydimethylsiloxane (PDMS) matrix and following a PLA/PDMS electrospun nanofiber coating as a temporary biointerface to promote early cell attachment. Composite patches (PDMS, PDMS+TiC, PDMS+MoS₂, and Hybrid) were fabricated by casting/curing and coated at a semi-cured stage to enable physical interlocking of the fiber layer. The materials were characterized by SEM, FTIR, XRD, XPS, wettability measurements, compressive testing, and TGA/DTGA. Electromechanical performance was assessed by cyclic compression (30% strain), and biological performance was evaluated using NIH3T3 fibroblasts (MTT, Live/Dead, and intracellular ROS assays) and H9c2 cardiomyoblasts on fiber-coated configurations under low-intensity agitation. The Hybrid patch exhibited balanced mechanical reinforcement and reproducible voltage generation (typically ±20-30 mV) under cyclic loading. All formulations maintained cytocompatibility, while the Hybrid group reduced intracellular ROS compared with single-filler composites and supported improved cell adhesion/spreading when combined with the nanofiber interface. These findings demonstrate a mechanically robust, electrically responsive, and cytocompatible PDMS-based hybrid scaffold with a degradable fibrous bio-interface, providing a foundation for self-powered, mechanically interactive cardiac patch platforms.