Hydrophobically modified poly(vinyl alcohol)s as antithrombogenic coating materials.

Hydrophobically modified poly(vinyl alcohol)s (hm-PVAs) with various alkyl chain lengths (3-12) were synthesized and were coated on poly(propylene) (PP) films. The blood compatibilities of the hm-PVAs-coated films were evaluated. The C6-PVA-coated PP film showed suppressed platelet adhesion as compared to the other hm-PVA-coated PP films, especially the 15C6-PVA-coated PP film, in which 30 mol% of OH groups were substituted by C6 groups. The fibrinogen adsorption was also inhibited on this film. The hydration water structure of the films was analyzed using differential scanning calorimetry (DSC). 15C6-PVA showed the highest (4.8 wt%) intermediate water (IW), and hence exhibited good blood compatibility. The fibrinogen γ chain activity of the 15C6-PVA-coated PP film was 18% lower than that of the PP film, indicating that hm-PVAs can inhibit fibrinogen γ chain activation. These results showed that by simple hydrophobic modification, PVA could be used as a blood contacting material.