A treatment of hydrophilic poly(hydroxyethyl methacrylate) contact lenses to minimize irreversible protein adsorption will be tested. Protein adsorption on lenses not only leads to clouding and opacities, but also induces what appears to be an immune response in the wearer. This response is observed in the early stages to include increased mucus production, mild itching, decreased lens tolerance and development of giant papillae in the upper torsal conjunction. Later stages exhibit a total loss of lens wearing tolerance. This study will be done both in vitro and in vivo. The in vitro studies will monitor irreversible protein adsorption on the control, as well as treated poly(hydroxyethyl methacrylate) surface using artificial tear solution. Two techniques, ESCA (X-ray photoelectron spectroscopy) and TIRIF (total internal reflectance intrinsic fluorescence) spectroscopy will be used in parallel to monitor protein adsorption to these surfaces. In vivo studies will incorporate a 10-day continuous wear test utilizing the rabbit as the animal model and will be done both in-house and through an independent testing lab. Again, both treated and control lenses will be used in this study. Retrieved lenses will be analyzed by optical microscopy and ESCA spectroscopy.
