BIOCOMPATIBILITY OF SYNTHETIC LENSES

THE CONVENIENCE AND OPTICAL ADVANTAGES OF CONTACT LENSES ARE PRODUCING A GROWING MARKET FOR BOTH THE EXTENDED-WEAR AND DAILY-WEAR PRODUCTS. A NEED REMAINS FOR IMPROVEMENTS IN THE BIOCOMPATIBILITY OF BOTH CONTACT (ESPECIALLY LONG-WEAR) AND INTRAOCULAR LENSES. IN MANY USERS, THE LONG-WEAR CONTACT LENSES LOSE OPTICAL CLARITY AND COMFORT THROUGH EXCESSIVELY RAPID ADSORPTION OF PROTEINS, CALCIUM, AND OTHER MINOR COMPONENTS FROM THE EYE FLUID AND TISSUE. THE IMPROVEMENT OR MAINTENANCE OF GAS (ESPECIALLY OXYGEN) PERMEABILITY AND NONINJURIOUS INTERACTION WITH THE CORNEA, IS NEEDED FOR LONG-WEAR CONTACT LENSES. THE DEVELOPMENT OF PROTECTIVE COATING FOR INTRAOCULAR LENSES TO DECREASE CORNEAL DAMAGE THROUGH CONTACT WITH THE DAMAGED CORNEA AT THE TIME OF SURGERY ALSO REMAINS A CURRENT NEED. THE CHEMICAL ""TAILORING'' OF PLASTIC SURFACES THROUGH PHOTOCHEMICAL COUPLING HAS BEEN DEMONSTRATED IN OUR LABORATORIES TO BE A PRODUCTIVE APPROACH TO BIOCOMPATIBILITY CONTROL. THROUGH EFFICIENT PHOTOCHEMICAL COUPLING UNDER VERY GENTLE REACTION CONDITIONS, THE SURFACE CHEMICAL PROPERTIES OF NUMEROUS PLASTICS HAVE BEEN MODIFIED THROUGH COVALENT ATTACHMENT OF NEUTRAL HYDROPHILIC OR HYDROPHOBIC POLYMERS, PROTEINS, AND OTHER CHARGED OR OTHERWISE FUNCTIONAL GROUPS. PRELIMINARY STUDIES ON THE PHOTOCHEMICAL ATTACHMENT OF HYDROPHILIC POLYMER DERIVATIVES TO THE SURFACE OF POLYSTYRENE, POLYURETHANE, AND POLY(HYDROXYETHYLMETHACRYLATE), HAVE DEMONSTRATED A MAJOR DECREASE IN THE SPONTANEOUS ADSORPTION OF A FEW PROTEINS EXAMINED. BIO-METRIC SYSTEMS PRESENTS A PLAN FOR TESTING THE EXPERIMENTAL FEASIBILITY OF BIOCOMPATIBILITY IMPROVEMENTS ON CONTACT AND INTRAOCULAR LENSES THROUGH THE PHOTOCHEMICAL ATTACHMENT TO THEIR SURFACES OF HYDROPHILIC AND OTHER CHEMICAL SIDE CHAINS WITH THE DESIRED CHEMICAL, ELECTROSTATIC, AND OTHER FUNCTIONAL PROPERTIES.