Colorless poly(vinyl pyrrolidone) hydrogel contact lenses synergized with silver nanoparticles

Biocompatible polymers such as poly(vinyl pyrrolidone) (PVP) are used to prepare hydrogels for biomedical applications, optical applications, cosmetic and smart medical contact lenses, and many other applications. However, the commercial PVP lenses available today are optically poor, and wearers of PVP medical contact lenses typically experience spherical, coma, astigmatism, and chromatic aberrations due to light dispersion when the pupil is opened at 2.50 mm. In this work, three contact lenses were prepared by doping PVP hydrogel with 0.1%, 0.5%, and 1% by weight of laboratory-manufactured silver nanoparticles (Ag NPs). This work demonstrates the evaluation of vision correction through each lens and the effect of changing the concentration of Ag NPs on its refractive index. The simulation included the design and simulation of an aberrated human eye based on the Liou and Brennan model and the insertion of the contact lenses for vision correction using the ZEMAX optical design program. The resulting refractive index of one PVP-Ag lens was relatively high at 532 nm = 1.545, leading the lens to guide light rays into a small spot of 3.983 µm root mean square and a highest image contrast (lowest MTF curve degradation) of 0.863 ± 0.027 at 20 cycles/mm.