“Click” Chemistry-Tethered Hyaluronic Acid-Based Contact Lens Coatings Improve Lens Wettability and Lower Protein Adsorption

Abstract

Improving the wettability of and reducing the protein adsorption to contact lenses may be beneficial for improving wearer comfort. Herein, we describe a simple "click" chemistry approach to surface functionalize poly(2-hydroxyethyl methacrylate) (pHEMA)-based contact lenses with hyaluronic acid (HA), a carbohydrate naturally contributing to the wettability of the native tear film. A two-step preparation technique consisting of laccase/TEMPO-mediated oxidation followed by covalent grafting of hydrazide-functionalized HA via simple immersion resulted in a model lens surface that is significantly more wettable, more water retentive, and less protein binding than unmodified pHEMA while maintaining the favorable transparency, refractive, and mechanical properties of a native lens. The dipping/coating method we developed to covalently tether the HA wetting agent is simple, readily scalable, and a highly efficient route for contact lens modification.

Contact Lens Materials: A Materials Science Perspective

“…These lenses retained an optical transparency level of >92%, and decreased the water contact angle and rate of lens dehydration. A more detailed mechanism of the covalent bonding of HA to the HEMA hydrogel structure was presented by Deng et al [166] “Click” chemistry was used with adipic acid dihydrazde (ADH) to anchor HA to HEMA. HEMA was first oxidized to provide the functionality for bonding the ADH-HA anchor.…”

“…; Hoare, T. “Click” chemistry-tethered hyaluronic acid-based contact lens coatings improve lens wettability and lower protein adsorption, ACS Applied Materials and Interfaces, 2016, 8, 22064. Copyright 2016 American Chemical Society [166].…”

Surface modification of model hydrogel contact lenses with hyaluronic acid via thiol-ene “click” chemistry for enhancing surface characteristics

“…60 Recently, Deng et al. 61 were able to improve the surface characteristics of pHEMA hydrogels by HA immobilization via hydrazone bonds using aldehyde–hydrazide chemistry. Although improved surface properties were observed, there are drawbacks with the methods used to synthesize the HA-hydrazide and the aldehyde-modified pHEMA surfaces, which limit control over the reaction and may also limit the scalability of the system.…”

Poly(2‐hydroxyethyl methacrylate)/boric acid composite hydrogel as soft contact lens material: Thermal, optical, rheological, and enhanced antibacterial properties

“…Soft contact lenses are prostheses using by millions of people all over the world to correct of visual disorders, changing eye color, or in the treatment of corneal diseases . Furthermore, soft contact lenses provide to the wearer's esthetic appearance, confidence and freedom .…”