Oligosachharide modified biomimetic surfactant polymer for non-thrombogenic interface applications: Platelet Adhesion Studies

Introduction The presence of proteoglycans, glycosaminoglycans and other glycosylated molecules is responsible for the inherent non-adhesive nature of the endothelial cell glycocalyx that prevents attachment of other cells and biomolecules to the intravascular endothelial cell lining . Mimicking such a sugar-rich structure for vascular interfacial biomaterials provides a way to prevent the clinical problem of thrombus formation on blood-contacting biomaterials used for vascular grafts, cardiovascular assist devices, device housings etc. Shear-induced adhesion and aggregation of activated platelets on biomaterial surfaces is a major cause of subsequent thrombotic events. The presence of a non-adhesive glycocalyx-mimetic interface between the biomaterial surface and blood would potentially suppress platelet interactions and hence impart non-thrombogenicity to the biomaterial surface. Based on this rationale, dextranmodified poly(vinyl amine) surfactant polymers were developed that adsorb spontaneously on a variety of polymeric biomaterials. The polymer consists of a flexible poly(vinyl amine) backbone with pendant hexanoyl groups for binding to a hydrophobic biomaterial surface and pendant dextran (oligosaccharide) side-chain that orient into the aqueous environment to provide a glycocalyx-mimetic interface. The chemical structure of the polymer is shown in Figure 1.