Stress-assisted gold micro-wrinkles on a polymer cantilever for cardiac tissue engineering

Surface topography of devices is crucial for cardiac tissue engineering. In this study, we fabricated a unique cantilever-based device, whose surface was structured with stress-assisted micro-wrinkles. The Au micro-wrinkle patterns on the cantilever surface helped the cardiomyocytes to grow similarly to those in the native cardiac tissues by aligning them and providing them a conductive surface, thereby enhancing the contractile properties of the cells. The patterned Au surface also enhanced the electrical conductivity during cell-to-cell interactions. Additionally, the expression levels of proteins related to intracellular adhesion and contraction significantly increased in the polymer cantilevers with metallic wrinkle patterns. The roles of the polymer cantilever in improving the electrical conductivity and force-sensing properties were confirmed. Thereafter, the cantilever's response to cardiotoxicity was evaluated by introducing drugs known to induce toxicity to cardiomyocytes. The proposed cantilever is a versatile device that may be used to screen drug-induced cardiotoxicity during drug development.