Improving hemocompatibility of polypropylene via surface-initiated atom transfer radical polymerization for covalently coupling BSA

Abstract

Bovine serum albumin (BSA) modified polypropylene (PP) was fabricated via surface-initiated atom transfer radical polymerization (SI-ATRP) of poly(ethylene glycol) methacrylate (PEGMA) and glycidyl methacrylate (GMA). Kinetics study revealed an approximately linear increase in graft density of the functional brushes with polymerization time. Attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy confirmed that comonomers and BSA were successfully immobilized onto PP film. The hydrophilicity of PP was improved by modification with PEGMA and GMA. The balance between the inhibition of BSA adsorption by PEGMA and the covalent immobilization of BSA by GMA through the ring-opening reaction of the epoxy group resulted in the moderate fluorescence intensity of FITC–BSA immobilized PP-g-P (PEGMA-co-GMA). The hemolysis test showed that BSA could decrease the hemolysis rate. Red blood cell membrane maximal stress can be reduced by the inertness of BSA as well as the repulsion caused by its electrostatic interactions. Whole blood cell attachment tests showed that BSA molecules weakened the interaction between blood cells and the PP surface. Therefore, the immobilization of BSA on PP film is an effective approach for improving the hemocompatibility of PP.