PHYSICAL PROPERTY ANALYSIS AND BACTERIAL ADHESION ON A SERIES OF PHOSPHONATED POLYURETHANES

Grycerophosphorylcholine (GPC) was incorporated as the chain extender in a series of poly(tetramethylene oxide)-based polyurethane block cop olymers. in order to determine the feasibility of use of these polyure thanes in biomedical devices, the effects of GPC incorporation on phys ical properties were studied. The effect of soft-segment molecular wei ght was also investigated. Biocompatibility of these materials was stu died with regard to bacterial adhesion and protein deposition. Tensile testing showed that as GPC content increased, elongation at break dec reased, while Young's modulus increased. Differential scanning calorim etry (DSC) results showed slightly decreased glass transition temperat ures (T(g)s) with increasing GPC content, indicating increased phase s eparation. Dynamic mechanical analysis (DMA) confirmed the decrease in T-g and the increase in rubbery plateau modulus with increasing GPC c ontent. Water absorption was also increased with GPC content. Decrease d bacterial adhesion was found on the GPC-containing materials compare d to other functionalized polyurethanes. These experiments were carrie d out in a radial flow chamber utilizing automated video microscopy. B acterial attachment was found to be lower on the GPC-containing polyur ethanes both in the absence of and after pre-adsorption with plasma pr oteins. (C) 1997 Elsevier Science Limited.