Synthesis and Hemocompatibility Evaluation of Novel Segmented Polyurethanes with Phosphatidylcholine Polar Headgroups

A new diol with a phosphatidylcholine polar headgroup, [bis(2-hydroxymethyl)]propane-2-(trimethylammonio)ethyl phosphate (BTEP), was synthesized and characterized. The BTEP, together with 1,4-butanediol (BD) as a chain extender, was used to synthesize segmented polyurethanes (SPUs) based on diphenylmethane diisocyanate (MDI) and various types of soft segments such as polycarbonate, polyether, polyester, and hydrocarbon diols. The bulk characteristics of the resulting SPUs were investigated by infrared (IR) spectroscopy, viscosity, and gel-permeation chromatography (GPC) measurements. Good mechanical properties of the typical SPU containing poly(butadiene) glycol (PBD) were indicated by dynamic viscoelasticity and tensile measurements. The phosphatidylcholine polar groups were oriented on the surface of these materials as revealed by attenuated total reflectance−Fourier transform infrared spectroscopy (ATR−FTIR), electron spectroscopy for chemical analysis (ESCA), and contact angle measurements. The hemocompatibilities of the new polymers were evaluated by platelet-rich plasma (PRP) contact studies and viewed by scanning electron microscopy (SEM) using medical BioSpan as a reference. The new materials have good surfaces in terms of platelet adhesion, and the morphology of adhered platelets undergoes a relatively low degree of variation. Suitably increasing percentages of phosphatidylcholine polar groups in the polymers and higher molecular weights of the soft segments of the polymers may further improve hemocompatibility.