Effect of the distribution of adsorbed proteins on cellular adhesion behaviors using surfaces of nanoscale phase-reversed amphiphilic block copolymers

In order to create suitable biocompatible materials for various tissue engineering applications, it is important to be able to understand protein adsorption and cell adhesion behaviors on the material's surfaces. It is known that the nanoscale distribution of adsorbed proteins affects cell adhesion behaviors. However, how nanoscale structures affect cell adhesion behaviors is still unclear. Therefore, in this study, we investigate the effect of the distribution of adsorbed proteins by the phase reversal of amphiphilic block copolymers composed of protein-non-adsorptive poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and protein-adsorptive poly(3-methacryloyloxy propyltris(trimethylsilyloxy) silane) (PMPTSSi) on cell adhesion behaviors. The nanodomain structures of phase-separated block copolymers were successfully confirmed using transmission electron microscopy and atomic force microscopy. Surfaces that had PMPC dot-like domains (23 +/- 4 nm) and ones that had PMPTSSi dot-like domains (25 +/- 6 nm) were made. From protein adsorption and L929 cell adhesion measurements, it was found that even on surfaces with equal quantities of protein adsorption, the number of cells on surfaces with PMPC dot-like domains was larger than those with PMPTSSi dot-like domains. This suggests that the simple phase-reversal of the distribution of adsorbed proteins can be used to affect cell adhesion behaviors for designing biomaterial surfaces for tissue engineering applications. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.