Competitive protein adsorption on polysaccharide and hyaluronate modified surfaces

Abstract

Adsorption of bovine serum albumin (BSA) and fibrinogen (Fg) was measured on six distinct bare and dextran- and hyaluronate-modified silicon surfaces created using two dextran grafting densities and three hyaluronic acid (HA) sodium salts derived from human umbilical cord, rooster comb and Streptococcus zooepidemicus. Film thickness and surface morphology depended on the HA molecular weight and concentration. BSA coverage was enhanced on surfaces in competitive adsorption of BSA:Fg mixtures. Dextranization differentially reduced protein adsorption onto surfaces based on oxidation state. Hyaluronization was demonstrated to provide the greatest resistance to protein coverage, equivalent to that of the most resistant dextranized surface. Resistance to protein adsorption was independent of the type of HA utilized. With changing bulk protein concentration from 20 to 40 μg ml⁻¹ for each species, Fg coverage on silicon increased by 4x, whereas both BSA and Fg adsorption on dextran and HA were far less dependent on protein bulk concentration.

Keywords:

• competitive protein adsorption
• HPLC
• biocompatible surfaces
• dextran
• hyaluronate
• biofouling

Acknowledgements

The authors are grateful to the NIH for support through grant R01 HL60230 (DME). Partial support was provided by the NSF Polymers (DMR05-49307), MRSEC (DMR05-20020) and NSEC (DMR04-25780) programs (LC, RJC). Thanks to Hyun-Su Lee and Daeyeon Lee for their assistance with zeta potential measurements. The authors appreciate Thomas P. Russell and Jack Hirsch (Materials Research Science and Engineering Center at University of Massachusetts) for XPS measurements.