UC Irvine

Approximately 2 million cases of microbial keratitis occur in the world every year. Microbial keratitis can develop into vision loss and other severe complications. The current treatment is the use of antibiotic eye drops, which have diminished effect due to the increasing development of antimicrobial resistance. Instead of using drugs to control microbe growth, we engineered an antimicrobial nanopillared topography onto a hydrogel material to physically inhibit microbe growth and reduce the risk of contact lens-related microbial keratitis. The challenges, thus objective of this research, is to develop a method to integrate the nanotopography onto curved lens surfaces and to stabilize the nanostructures by crosslinking the hydrogel polymer. The hydrogel chitosan has antimicrobial and mucoadhesive properties that can promote wound healing. The dimensions and curvatures of the lens need to be controllable after the material is saturated with solvent. Chitosan hydrogels are stabilized by co-crosslinking with a covalent crosslinker, genipin (GP), and ionic crosslinker, tripolyphosphorous (TPP), or single crosslinking with only TPP. The material properties are modulated and characterized to suit the contact lens application. The antifungal properties of the engineered contact lens are also characterized with in vitro tests. The result shows that the resulting ophthalmic device is able to stabilize the nanotopography and hinder Fusarium oxysporum growth on the device surface for 24 hours.