Hemoglobin adsorption to three polymer surfaces

Protein adsorption to artificial surfaces implanted in the cardiovascular system is believed to play an important role in thrombosis induced by these materials. Previously, hemoglobin adsorption has not been considered important because very little of this protein is usually present outside of red cells. However, the highly preferential adsorption of hemoglobin to polyethylene was recently reported (22). In this study, the adsorption of hemoglobin, albumin, fibrinogen and γ-globulin from plasma to three polymers were quantitatively measured. The polymers were polyethylene; the hydrogel, polyhydroxyethylmethacrylate; and its hydrophobic homolog, polyethylmethacrylate. Hemoglobin adsorption to these surfaces from plasma was also detected electrophoretically. The adsorbed protein layer on these surfaces was found to be greatly enriched in hemoglobin relative to the bulk plasma composition. The high affinity of hemoglobin for these diverse polymer surfaces suggests the prime role of fibrinogen in adsorption from plasma should be re-evaluated.