Deposition of a hydrophilic nanocomposite-based coating on silicone hydrogel through a laser process to minimize UV exposure and bacterial contamination

To prevent contact lens from biofouling and to minimize UV exposure to human eyes, a nanocomposite-based coating made of silver (Ag) nanoparticles and polyvinylpyrrolidone (PVP) is deposited on synthetic silicone hydrogels through matrix assisted pulsed laser evaporation (MAPLE) with a pulsed Nd:YAG laser at 532 nm. The average diameter of Ag NPs that have undergone the MAPLE process for 60 min is 11.61 +/- 3.58 nm. The thickness of the Ag-PVP nanocomposite coating with a deposition time of 60 min is around 930 +/- 15 nm. Our results demonstrate that the oxygen permeability of silicone hydrogel with a nanocomposite coating is similar to that of commercialized contact lenses; over 60% of UV light in the range of 300-450 nm can be blocked. Moreover, the silicone hydrogel with the nanocomposite coating can reduce over 65.4 +/- 1.6% of protein (human lysozyme) absorption as compared to silicone hydrogel-based contact lens, and kill all cultured bacteria in 8 hours. This research work demonstrates a new way to deposit biocompatible nanocomposite coatings on silicone hydrogels used as contact lens to efficiently minimize UV exposure and biofouling.