Surfaces for heart cells:Establishing the optimum plasma surface engineering methodology on polystyrene for cardiac cell engineering

International audiencePlasma surface modification is a popular method for improving cellculture on surfaces, and polystyrene (PS) is literature’s materialof choice. This study identifies the optimum plasma treatment forpromoting normal cardiac cell behaviour during culture. PS slideswere plasma-treated with O2, N2, O2 + N2 and Ar + N2 for 20 and 30min in a reactive ion etcher (RIE). SEM reveals that O2 and O2 + N2plasmas create dual scale roughness, N2 plasma creates oval-shapedstructures, while Ar + N2 exhibits no topography. Evaluation by XPSreveals an increase in the atomic percentage of oxygen for alltreatments. Contact angle measurements agree as all treatments leadto hydrophilisation, with N2 samples exhibiting long-term stability. Two sources of cells were used to identify the optimum plasma treatment for cardiac cell culture on PS. H9c2 cells exhibit optimal ehaviour with N2 and N2 + Ar regarding viability, morphology, and focal adhesion contact. The same was observed for primary cardiomyocytes on N2 samples. For purified cardiomyocytes, immunofluorescence revealed well-organised sarcomeric structure on N2 samples, exhibiting clear improvement compared to control. SEM validated these findings, as cardiomyocytes on N2-treated PS exhibited physiological, elongated shape. These findings provide solid evidence that the optimum treatment for PS is the use of N2 plasma