Interactions of plasma proteins with a novel polysaccharide surfactant physisorbed to polyethylene

—A polysaccharide surfactant, dextran-[1,6 bis(2-hydroxypropyl-1-amine)hexane]-dextran, (D-H-D) was prepared by reacting dextran (M_w = 8200) with epichlorohydrin followed by reaction with 1,6-hexanediamine. The D-H-D polymer product was characterized by gel permeation chromatography (GPC), and ¹³C-nuclear magnetic resonance spectroscopy (¹³C-NMR). D-H-D was physisorbed on polyethylene (PE) from aqueous solution, and the adhesion stability and resistance to protein adsorption was examined under static and dynamic flow conditions, using a modified rotating disk system. Modified surfaces were characterized by attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR), electron spectroscopy for chemical analysis (ESCA) and by water contact angles. Under applied shear stresses of up to 73 dyn cm^-2, the adhesion of D-H-D on PE was sufficient to inhibit desorption by water (>90% D-H-D on PE was retained) and 5% SDS surfactant solution (approximately 83% D-H-D retained), as determined by ATR-FTIR. Under similar shear stress conditions, albumin adsorption on D-H-D modified PE was reduced by over 90%, and protein adsorption from fresh human plasma was reduced by approximately 70% compared with unmodified PE. The results are discussed in terms of interfacial forces, and the suitability of this approach for studying protein-surface interactions and for developing a novel class of protein-resistant biomaterials.