Electrostatically Engineered Polyoxometalate Contact Lenses for Integrated Shielding of UV Radiation and Ozone-Induced Ocular Stress

Abstract

The eyes are highly vulnerable to environmental stressors like air pollution and ultraviolet (UV) radiation, often resulting in ocular diseases, yet current protective strategies remain fragmented and transient. This study presents a functionalized nanocomposite contact lens for ocular health improvement, featuring visual clarity, UV protection, antioxidant activity, and oxygen supply. A co-polymerization strategy is introduced by employing cationic [2-(methacryloyloxy)ethyl]trimethylammonium chloride (DMC) into traditional gel-like contact lenses, transforming them from a dense to a porous structure. This method significantly enhances the loading capacity of a reactive oxygen species (ROS) scavenger, dark blue molybdenum (Mo⁵⁺)-based polyoxometalate (POM), via electrostatic interactions. Selective oxidation of Mo⁵⁺-POM to colorless Mo⁶⁺-POM within the optical zone yields the DMC-POM-based cosmetic contact lens (DPCCL), which maintains commercial-grade clarity while exhibiting superior UV shielding and ROS scavenging capabilities. Furthermore, during ROS scavenging, DPCCL generates oxygen and undergoes color changes, enabling prolonged wear and providing a visual indicator for ROS elimination monitoring. Both in vitro and in vivo studies confirm that DPCCL reduces pro-inflammatory cytokines, preserves corneal epithelial integrity, and alleviates ozone-induced dry eye symptoms. These findings establish DPCCL as a continuous and proactive ocular protection platform, providing a comprehensive solution for maintaining ocular surface health against environmental oxidative stress.