Document Type : Research Paper
In order to increase the water content and the oxygen permeability of hydrogels used in the
manufacture of contact lenses, the polar monomer Silicon Hydrogel Contact Lenses (SHCL), and 2-
hydroxyethyl methacrylate (HEMA) were copolymerized with the hydrogels. Due to the presence of
polar monomers in the conventional contact lenses, the major component of the human tear,
lysozyme is extensively adsorbed onto their surfaces. The adsorption of lysozyme onto the contact
lens’ surface leads to limitations in its application. The present study concentration of lysozyme,
adsorbed onto the surface of HEMA and SHCL hydrogels were measured by UV-Vis spectroscopy.
The lysozyme employed was obtained from solutions with similar to concentration of artificial tear.
The adsorption results were examined by the Langmuir adsorption isotherm and the constants of this
isotherm were also evaluated.