Plasma modification of heparinised CNT/PU nanocomposite and measuring of mechanical, calcification and platelet adhesion properties for application in heart valve

Abstract

ABSTRACT In this study, the calcification and platelet adhesion resistance property of plasma-treated polyurethane/heparinised carbon nano tube (PU/HCNT) nanocomposite thin films as a candidate polymer for polymeric heart valve was investigated. The PU and HCNTs nanocomposite films (PU/HCNT) were prepared using the solvent casting technique. CNTs were heparinised to surpass the dispersal and calcification resistance of CNTs in the PU matrix. Dispersal of CNTs in the matrix of produced films was analysed with (TEM), and HCNTs were observed well distributed in the polymer matrix. Greater storage modulus and better calcification resistance were detected for the nanocomposite. DMTA used for determining nanocomposite properties, which showed that the modulus increased as modified CNTs added to the matrix. The composite films were exposed to oxygen plasma treatment. The modified surface was characterised using ATR-FTIR, SEM, EDXA, and water drop contact angle measurements. The results indicated that the treated PU/HCNT surface was more hydrophilic. Increased surface roughness for modified PU/HCNT surface observed in AFM images. In-vitro calcification test verified reduced calcification for the modified PU/HCNT surface. No cytotoxicity was observed for the modified polymeric films using L929 fibroblast cells. The platelet adhesion test showed that the modified films are more blood compatible than unmodified.