Metal-phenolic conducting polymer hydrogels for multifunctional cardiac patches and post-infarction myocardial repair.

Myocardial infarction (MI) causes irreversible cardiomyocyte loss and adverse ventricular remodeling, yet current cardiac patches remain limited by inadequate bioactivity and poor electrical integration with host myocardium. We report a multifunctional metal-phenolic conducting polymer hydrogel (CPH) for post-infarction myocardial repair. A one-pot process integrates a conductive polypyrrole network with dynamic Cu2+-tannic acid (TA) coordination, thereby combining electrical conductivity, mechanical support, and redox-related functionality within a single hydrogel. Cu-TA CPH exhibited myocardium-matched mechanical properties (∼19 kPa), suitable conductivity, good biocompatibility, and intrinsic antioxidant and antibacterial activities. These combined features enabled the hydrogel patch to provide mechanical support, facilitate electrical communication, and improve the local microenvironment after MI. On postoperative day 7, left ventricular ejection fraction in the Cu-TA CPH-treated MI group was higher than that in the MI group receiving no material treatment. This therapeutic effect was associated with an increased Bcl-2/Bax ratio, enhanced VEGFR-1 expression, reduced infarct size, and improved myocardial tissue preservation. Collectively, Cu-TA CPH represents a promising hydrogel patch for post-infarction myocardial repair.