Optimization of a PDMS-Based Cell Culture Substrate for High-Density Human-Induced Pluripotent Stem Cell Adhesion and Long-Term Differentiation into Cardiomyocytes under a Xeno-Free Condition

Despite the numerous advantages of PDMS-basedsubstrates in various biomedical applications, they are limited bytheir highly hydrophobic surface that does not optimally interactwith cells for attachment and growth. Hence, the lack of lengthyand straightforward procedures for high-density cell production onthe PDMS-based substrate is one of the significant challenges incell production in the cell therapyfield. In this study, we found thatthe PDMS substrate coated with a combination of polydopamine(PDA) and laminin-511 E8 fragments (PDA + LME8-coatedPDMS) can support human-induced pluripotent stem cell (hiPSC)attachment and growth for the long term and satisfy their demandsof differentiation into cardiomyocytes (iCMs). Compared withprior studies, the density of hiPSCs and their adhesion time on thePDMS surface were increased during iCM production. Although the differentiated iCMs beat and produce mechanical forces, whichdisturb cellular attachments, the iCMs on the PDA + LME8-coated PDMS substrate showed dramatically better attachment than thecontrol condition. Further, the substrate required less manipulation by enabling one-step seeding throughout the process in iCMformation from hiPSCs under animal-free conditions. In light of the results achieved, the PDA + LME8-coated PDMS substrate willbe an up-and-coming tool for cardiomyocyte production for cell therapy and tissue engineering, microfluidics, and organ-on-chipplatforms.