Release of Betaine and Dexpanthenol from Vitamin E Modified Silicone-Hydrogel Contact Lenses

Abstract

Purpose: To develop a contact lens system that will control the release of an osmoprotectant and a moisturizing agent with the aim to reduce symptoms of ocular dryness.

Materials and methods: Profiles of the release of osmoprotectant betaine and moisturizing agent dexpanthenol from senofilcon A and narafilcon B contact lenses were determined in vitro under sink conditions. Both types of lenses were also infused with vitamin E to increase the duration of drug release due to the formation of the vitamin E diffusion barriers in the lenses. The release profiles from vitamin E-infused lenses were compared with those from the control lenses.

Results: Both dexpanthenol and betaine are released from commercial silicone hydrogel lenses for only about 10 min. Vitamin E loadings into contact lenses at about 20–23% can increase the release times to about 10 h, which is about 60 times larger compared to the control unmodified lenses.

Conclusions: Vitamin E-loaded silicone hydrogel contact lenses released betaine and dexpanthenol in a controlled fashion.

• Betaine
• contact lens
• controlled release
• dexpanthenol
• ocular discomfort
• vitamin E

Declaration of interest

Anuj Chauhan is a co-inventor on US patent 8404265 “Contact lenses for extended release of bioactive agents containing diffusion attenuators”. This research was partially supported by a research grant from the National Science Foundation (CBET CMMI grant 1129932).