Thrombin and factor XIIa generation in plasma contacting polyurethane surfaces: Effect of surface immobilized PPACK

The tripeptide phe-pro-arg-chloromethylketone (PPACK), a direct, specific and potent thrombin inhibitor used in improving polyurethane surfaces for blood contact, have been investigated. The expectation is that such materials would act as scavengers of thrombin generated via surface initiated coagulation. The effectiveness of such surfaces was assessed using a chromogenic substrate assay to measure the generation of thrombin plasma.