Surface functionalisation of contact lenses by CS/HA multilayer film to improve its properties and deliver drugs

Abstract

Soft contact lenses are very popular for vision correction and cosmetic alterations since 1960. However, wearing soft contact lenses induced many healthy problems, which are often related to the surface properties of contact lenses such as low wettability and protein deposition. Chitosan (CS)/Hyaluronic acid (HA) multilayer was assembled on the surface of contact lenses by layer-by-layer (LbL) technique to improve the surface properties of low wettability and protein deposition in the research. Surface modification improved the hydrophilic, reduced protein adsorption, enhanced water retention and increased the surface roughness length. Since LbL self-assembled multilayer films were proved to deliver drug effectively, norfloxacin and timolol as model drugs were loaded into CS/HA multilayer during LbL process. The contact lens with CS/HA multilayer could control norfloxacin steadily release in 1 h, timolol steadily release in half an hour. The novel aspect of the research is the construction of CS/HA multilayer on the surface of contact lenses for improving their surface properties and drug delivery. The impact of the research concerns the applications of multilayer and LBL technique, which opens up a useful way to decrease the problem of wearing hydrogel contact lenses and increase the possibility of hydrogel contact lenses as drug carrier.