Radiation induced modification of polyetherurethane films and tubes: Platelet adhesion and in vivo experiments

The measurement of platelet adhesion to polyetherurethane films grafted (via the preswelling technique) with 2-hydroxyethyl methacrylate (HEMA) and acrylamide (AAm), performed by means of the stagnation point flow experiment (SPFE-test) as well as with the aid of the bioluminescence assay, is described. Platelet adhesion is found to decrease if the interfacial free energy γ_sw of the polymer surfaces decreases. Adhesion to protein-coated, grafted polyetherurethane films (coated with albumin, γ-globulin, fibrinogen, fibronectin or a protein mixture) depends on the nature of the protein used: precoating of the films with albumin of γ-globulin leads to a decrease, precoating with fibrinogen or fibronectin to an increase in platelet adhesion.

Also we report about early experiences with HEMA-grafted polyetherurethane tubes in implantation experiments.