SILICONE-PROTEIN FILMS - ESTABLISHING THE STRENGTH OF THE PROTEIN-SILICONE INTERACTION

Protein-on-silicone and silicone-on-protein films were prepared using either trimethylsilyl-terminated (unfunctionalized, PDMS) or (triethox ysilyl)propyl-terminated (functionalized, TES-PDMS) silicones and huma n serum albumin (HSA). The films were exposed to aqueous solutions of different pH's or containing SDS. X-ray photoelectron spectroscopy (XP S) and contact-angle measurements (CA) were used to characterize the r esulting surfaces. The film formed by coating a protein surface with T ES-PDMS showed much slower protein desorption kinetics than the other slides upon challenge by SDS, acidic, neutral, or basic aqueous soluti ons. This observation may be understood to arise from the cross-linkin g of TES-PDMS using the protein as a template, resulting in intimate c ontact between the two polymers.