Adhesion and aggregation of thrombin prestimulated human platelets: evaluation of a series of biomaterials characterized by ESCA.

Five materials of interest in blood contact applications (PVC, Silastic, Biomer and siliconized glass) were internally coated on glass tubes and exposed to suspensions of platelets and red cells. Uncoated glass was also examined. Thrombin was added (prestimulation) to some suspensions before exposure to the biomaterial surfaces. The three polymeric surfaces were characterized by electron spectroscopy for chemical analysis (ESCA). Prestimulation with thrombin leads to increased adhesion of single platelets only with Silastic. With a wide range of surface types, thrombin prestimulation consistently leads to higher levels of platelet accumulation in the form of aggregates; the PVC-coated material showed the highest levels. ESCA analysis of PVC, however, suggested our coating was impure or an oxidized material.