3D printed iron oxide nanozyme contact lenses for oxidative stress reduction

3D printing facilitates a wide range of novel possibilities for ocular healthcare. 3D printed therapeutic contact lenses can be useful for the prevention and treatment of ocular diseases like dry eye syndrome and bacterial keratitis. This work explores 3D printed iron oxide nanozyme incorporated contact lenses for oxidative stress reduction. Iron oxide nanoparticles can behave as nanozymes, providing oxidative stress reduction in the eye. Here, 2-hydroxyethyl methacrylate (HEMA) and polyethylene glycol diacrylate (PEGDA) lenses are 3D printed, and iron oxide nanoparticles are then incorporated within these lenses through in situ precipitation. Nanoparticle formation and catalytic activity are studied for different HEMA: PEGDA ratios. The nanoparticle concentration was found to increase with HEMA ratio in the hydrogel. Nanozyme lenses displayed catalytic activity in the presence of hydrogen peroxide, demonstrating their oxidative stress reduction capabilities. While HEMA: PEGDA 100:0 ratio had the largest nanoparticle concentration, HEMA: PEGDA 75:25 was the best for catalytic activity and methylene blue removal. All the nanozyme lenses exhibited good cell viability with human dermal fibroblasts. In addition to cytocompatibility, HEMA: PEGDA 75:25 lenses displayed significant cytokine suppression, establishing them as a promising candidate for safe, multifunctional contact lens applications. Hydrogels with iron oxide nanoparticles also respond to external magnetic fields due to the superparamagnetic property of these nanoparticles. The results indicate that there is great potential for the production of iron oxide nanozyme contact lenses with tunable properties through 3D printing.