Multifunctional contact lens sensor for tear protein analyses

This work reports the development of the first multifunctional bioinspired contact lens sensor which combines enhanced optical and bactericidal properties as well as protein sensing in tears for ocular diagnostics. We created glasswing-butterfly-inspired nanostructures using biocompatible parylene C and integrated them onto the surface of traditional scleral lenses. The nanostructure-integrated lenses minimize glare by 4.3-fold at 80 degrees, improve VIS transmission by 1.1-fold, and block 2.8-fold more UVA compared to their traditional counterpart. Furthermore, the parylene nanostructures physically lyse Escherichia coli in vitro (dead: 89% in 4 hrs). Finally, when coated conformally with metal, we used the same nanostructures to sense lysozyme and lactoferrin (dry eye disease biomarkers) label-free in human tears using Raman spectroscopy. Detection is performed in 8 whole human tear samples, demonstrating good agreement (+/- 0.27 mg/mL) with results produced using commercial ELISAs while reducing the diagnosis time by 16-fold with simpler sample preparation.