(549j) Effect of Protein Adsorption On Dewetting of Silicone Hydrogel Contact Lens Materials

Contact lens related discomfort and dryness is a major complaint amongst soft contact lens wearers. Previous studies have shown that over time, proteins from the tear film accumulate on the surface of a contact lens, leading to reduced wettability of the lens and ultimate dry eyes. In order to better understand this phenomenon, the Fuller lab has developed an apparatus to measure the dewetting of pure water films on a contact lens material. Lenses are stretched flat on an elevation stage built on a miniature Langmuir trough. By raising the stage, the lens surface captures a sessile droplet. Liquid is slowly drained and dewetting dynamics captured using a CCD camera. Film thickness is verified using laser interferometry.

We discuss the consequences of the adsorbed proteins on the dewetting dynamics of pure water on different contact lens hydrogel materials. Our findings indicate that adsorbed lysozyme modifies the surface heterogeneity and hydrophobicity of the hydrogel surfaces leading to increased dewetting.