Non-Biofouling Fluorinated Block Copolymer Coatings for Contact Lenses

Films of two fluorinated block copolymers (P(S81-Sz6) and P(S81-Sz11)) were investigated and compared with those of a commercial Teflon-like polymer (PTFE-AF) in the search for novel non-biofouling coatings able to minimize the amount of tear fluid (TF) proteins absorbed on contact lens (CL) surfaces. The adsorption of a solution containing lysozyme, albumin and immunoglobulin G (mimicking the TF composition) on the fluorinated block copolymers was evaluated using a quartz crystal microbalance. P(S81-Sz11) was found to resist protein adsorption more effectively than P(S81-Sz6) and PTFE-AF. The different interaction of P(S81-Sz6) and P(S81-Sz11) with the artificial TF was attributed to creation of a more heterogeneous and moderately hydrophobic surface of the latter polymer film by dynamic contact angle and atomic force microscopy studies. Moreover, deposition of P(S81-Sz11) on a CL-like silicone (PDMS) and a CL thin films demonstrated a protein adsorption reduction of up to 70% relative to pristine PDMS and commercial CL thin films.