ES-HS from blood vessels —A potent substance for inert nonthrombogenic polymers

Abstract

Two different membranes, a cellulose (visking dialysis tubing) and a polyethercarbonate membrane (Gambrane ®), were chemically modified: 1. (I)partially substituted 2-hydroxy-3-(trimethylammonionochloride)-propylcellulose 2. (II)partially substituted 12-aminododecanyl-desoxiamino-cellulose, partially cationized with 3-chloro-2-hydroxypropyl-trimethylammonium chloride 3. (III) partially substituted (3-aminopropyl)-amidosulfonyl-poly[etherearbonate], partially cationized with 3-chloro-2-hydropropyl-trimethylammoniumchloride. 4. (IV)partially substituted N-(2-aminoethyl)-imidocarbamate-cellulose. 5. (V)partially substituted N-(3-aminopropyl)-amidosulfonyl-poly[ethercarbonate]. A commercially available mucosa heparin (HE) was bound ionically to I–V. An endothelial cell surface heparan sulfate (ES-HS) was bound ionically to I and III. Furthermore, functional groups (COOH) of ionically-immobilized HE on I–V and ES-HS on III were subsequently bound covalently to functional groups (OH, NH 2) of the modified membranes. Platelet adhesion tests in a modified Baumgartner chamber were used to characterize the HE and ES-HS modified membranes. ES-HS ionically bound to I and ES-HS covalently bound to III led to surfaces completely inert to platelet adhesion. In contrast to these results, HE showed 100% and 80% platelet adhesion, respectively. These results show that ES-HS, which is responsible for the very high standard of nonthrombogenicity of the blood vessel wall, is a promising coating substance to achieve nonthrombogenic artificial surfaces.