Analyses of equilibrium water content and blood compatibility for Poly(2-methoxyethyl acrylate) by molecular dynamics simulation

Water structures of hydrated polymers have been suggested to directly influence the biomolecules' adsorption. We conducted a serial of molecular dynamics simulations to investigate the water structures of hydrated poly(2-methoxyethyl acrylate) (PMEA). According to the calculated IR spectra of water molecules categorized into four binding sites in hydrated PMEA, most of water molecules at water content less than 3 wt% are water molecules interacting with two carbonyl groups, corresponding to experimental observed non-freezing water. In addition, we found two-stage variation of the non-bound water content with increasing the water content. The turnover point can be regarded as the saturation point and be used to estimate the equilibrium water content (EWC). Furthermore, the ratio of bound water content to polymer oxygen content was found to be a possible index for predicting the platelet adhesion of polymers. The findings will be useful for developing new biomaterials containing oxygen moieties in the medical applications.