Investigating the blood compatibility of metallocene polyethylene subjected to steam treatment

Abstract

In this study, one of the green surface modification techniques, steam treatment was employed to improve the surface characteristics and haemocompatibility of metallocene polyethylene (mPE). The mean contact angle of untreated mPE (87.4º) decreased sharply for steam exposed mPE (60.25º). The increased surface roughness was demonstrated by atomic force microscopy (AFM), scanning electron microscopy (SEM) and Hirox 3-D microscopy. The mean roughness (Ra) of control mPE (2.757 nm) was increased to 8.753 nm by steam treatment, showed enhanced hydrophilicity. Fourier transform infrared spectroscopy (FTIR) analysis illustrated no chemical changes but the changes in absorbance intensity ensures the morphological changes in the treated samples. The blood compatibility studies were assessed by coagulation assays, haemolysis and platelet adhesion tests. The coagulation assays indicated a delay in clotting time on the steam exposed surface whereas haemolysis and platelet adhesion were significantly reduced. The green surface modification of mPE using steam enhanced its surface properties and haemocompatibility. The improved blood compatibility of mPE may help in efficient designing of haemocompatible biomaterials like cardiovascular implants.