Negative cilia model for biocompatibility: Sulfonated PEO-grafted polymers and tissues

Abstract

To improve the biocompatibility of polyurethane (PU) and bioprosthetic tissue (BT), they were chemically grafted with a hydrophilic poly(ethylene oxide) (PEO) and further negatively charged sulfonate groups (SO3) to produce PU-PEO-SO3 and BT-PEO-SO3, respectively. PU-PEO-SO3 was much more blood compatible than untreated PU and PU-PEO, and the degree of surface cracking and calcification on implanted PUs was decreased in the following order: PU > PU-PEO > PU-PEO-SO3. Also, less calcium deposition of BT-PEO-SO3 than that of BT control was observed in in vivo animal tests. Such superior blood compatibility, biostability, and anticalcification of sulfonated PEO-grafted PUs and tissues might be attributed to synergistic effects of nonadhesive and mobile PEO and negative sulfonate acid groups via a negative cilia model.