Hemocompatible Surfaces Through Surface-attached Hydrogel Coatings and their Functional Stability in a Medical Environment.

Blood compatible materials are a well-researched scientific field as such materials are required in a wide range of applications, for example, in heart-lung machines or ventricular assist devices. Surfaces coated with certain surface-bound neutral, water-swellable polymer networks have the ability to repel cells such as platelets and exhibit a significantly improved hemocompatibility. In this study, we investigate the interaction of platelets from whole blood with surfaces coated with photochemically generated surface-attached polymer networks based on polydimethyl acrylamide. As substrates medical-grade polyurethanes are used, and the networks are formed and attached to the substrate surfaces through C-H insertion reactions. The hydrogel-coated substrates are perfused with blood for extended periods of time. We show that the polymer coating prevents the adhesion of cells even at longer times of blood contact, regardless of the thickness of the coating employed. The surfaces can be sterilized following a standard autoclave procedure without any loss of function. Additionally, it is shown that the samples can be stored at least for 3 months under varying ambient conditions while retaining their functionality. The excellent blood compatibility, the possibility to coat even rather inert polymeric materials and the ability to handle the materials in an environment typical for a medical application make such coatings a promising candidate for future hemocompatible devices.