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 (esp. 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 (esp. oxygen) permeability and non-injurious interaction with the cornea, is needed for long-wear contact lens. 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 National Eye Institute recognizes these needs for technology development and has requested small business innovative research proposals in the PHS Omnibus Solicitation-SBIR. 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 added. 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.
