Hydroxyethyl Methacrylate Corneal Contact Lenses Doped with N-Vinylpyrrolidone and Silane-Modified Silica Nanoparticles for Enhanced UV Absorption

Despite the significant advancements in hydrogel materials, contemporary hydrogel contact lenses still need to protect against ultraviolet rays. This study explores the impact of silane-modified silica nanoparticles (SMSi nanoparticles) and N-vinylpyrrolidone (NVP) on the properties of hydroxyethyl methacrylate (HEMA) corneal contact lenses. The average diameter of SMSi nanoparticles was 300 ± 100 nm, and in situ copolymerization was employed to create poly(HEMA-NVP-SMSi) hydrogel contact lenses. The enhanced ultraviolet–visible (UV)-absorbing hydrogel materials were analyzed for their structural, optical, and performance properties, including water content, oxygen permeability, and stability. The findings indicated that NVP increased the hydrophilicity of the material while the silica nanoparticles effectively absorbed ultraviolet rays and underwent modifications to reduce aggregation. Moreover, the oxygen permeability of the hydrogel lenses is more than double that of pure pHEMA lenses, demonstrating excellent stability and safety.