Surface attached ultrathin polymer monolayers for control of cell adhesion

Background. Calcific degeneration is the major drawback of bioprostheses. None of the numerous preventive approaches omitted calcification. Previous studies showed that cellular surface seeding decreases calcium uptake in vitro but achievement of coverage remains problematic. A new approach is presented masking glutaraldehyde residues with a polymer layer allowing cell seeding. The aim of this study was to evaluate different polymers for suitability. Methods. Ten polymers-covalently bound to glass-were tested for their ability to seed animal and human cells. Quality of coverage was evaluated by light and scanning electron microscopy, and polymers were characterized physicochemically. Results. Quality of cellular growth was similar for canine and human cells. Five polymers allowed excellent surface coverage, two led to a decrease of cell adherence, and four to poor cellular growth. No correlation between molecular weight, thickness, hydrophilicity, or charge of the polymer and cell growth was found. Conclusions. Polymer monolayers can promote cellular growth but without correlation to physicochemical characteristics. Polymers covalently bound to biologic tissue appear to be a promising approach for achieving cellular coverage of biomaterials. (C) 2001 by The Society of Thoracic Surgeons.