Synthesis of polyurethane-g-poly(ethylene glycol) copolymers by macroiniferter and their protein resistance

We have synthesized polyurethane (PU)-g-poly(ethylene glycol) (PEG) copolymers for protein resistance. A macroiniferter consisting of polyurethane (PU) with tetraphenylethane groups is synthesized by the reaction of 1,1,2,2-tetraphenyl-1,2-ethanediol and isocyanate-terminated prepolymer with poly(tetramethylene glycol) (PTMG) segments. Such a macroiniferter initiates the polymerization of poly(ethylene glycol) methyl ether methacrylate to yield the target copolymer. Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy ((1)H NMR) and thermal analysis confirm the structure of the copolymer. Thermogravimetric analysis (TGA) also shows that the introduction of PEG side chains slightly decreases the thermal stability of the polymer. By use of quartz crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR), we have investigated the adsorption of fibrinogen, bovine serum albumin (BSA) and lysozyme on a PU-g-PEG surface in real time. It shows that the PU-g-PEG surface can resist protein adsorption depending on the PEG content.