Physical Properties of High Functional Contact Lenses with Hydrophilic Substance and Graphene Oxide Nanocolloids

J Nanosci Nanotechnol. 2020 Aug 1;20(8):4860-4865. doi: 10.1166/jnn.2020.17819.

Abstract

The purpose of this experiment is to evaluate the physical properties of contact lenses made by adding hydrophilic Hyaluronic acid (HA) and Methacrylic acid (MA) as additives and Graphene oxide nanocolloids. As a contact lens, AIBN (Azobisisobutyronitrile) was used as an initiator with HEMA (2-hydroxy methyl methacrylate) and EGDMA (ethylene glycol dimethacrylate) as a cross-linker. Hyaluronic acid (HA) and methacrylic acid (MA) were added at 5%, respectively. Graphene oxide nanocolloids were added at 0.1%, 0.3% and 0.5%, respectively. Each prepared contact lens was hydrated in 99% NaCl saline solution for 24 hours. And the basic physical properties of contact lenses were evaluated and compared. The refractive index of the sample with hyaluronic acid and MA added was 1.4390, which was not significantly different from that of the basic combination contact lens sample. When Graphene oxide nanocolloids, a nanomaterial, were added, the refractive index decreased with increasing amount of Graphene oxide nanocolloids from 1.4209 to 13959. In the case of water content, the sample with 5% Hyaluronic acid and MA added slightly increased to 41.01%. In the case of Graphene oxide nanocolloids added, 48.76%~53.56% of Graphene oxide nanocolloids were added. Especially, it was observed that the water content increased sharply in the 0.1% sample of Graphene oxide nanocolloids. When the amount of graphene oxide nanocolloids added to the contact lens material was increased, the refractive index, which is a basic physical property, gradually decreased as the contact lens material was added together with Hyaluronic acid, MA, and Graphene oxide nanocolloids added as a nanomaterial. The water content tended to increase gradually. Therefore, the combination of Graphene oxide and hydrophilicmaterials shows a synergistic effect of physical properties, which is considered to be suitable as a material for contact lenses.