Figure 4.

Platelet counts performed after whole-blood incubation with the studied materials (soluble heparin concentration 1.5 IU ml⁻¹). The reduction in platelet number is expressed as percentage of the values obtained for the 0 min samples. A significant improvement in platelet reduction is achieved by heparin coating the composite material. Results also indicated the stability of the heparin coating when the heparinized composite is repeatedly reduced and oxidized. The values represent the mean ± s.e. of the mean from experiments using blood from 10 different donors. (H, heparinized composite; H Red-Ox, heparinized composite after reduction–oxidation cycles; NH, non-heparinized composite; CA, cellulose acetate; RC, regenerated cellulose; PS polysulphone, 0.2 represents 0.2 µm pore size and 0.45 indicates membranes with 0.45 µm pore sizes).