Extended release of hyaluronic acid from hydrogel contact lenses for dry eye syndrome

Abstract

Current dry eye treatment includes delivering comfort enhancing agents to the eye via eye drops, but low residence time of eye drops leads to low bioavailability. Frequent administration leads to incompliance in patients, so there is a great need for medical device such as contact lenses to treat dry eye. Studies in the past have demonstrated the efficacy of hyaluronic acid (HA) in the treatment of dry eyes using eye drops. In this paper, we present two methods to load HA in hydrogel contact lenses, soaking method and direct entrapment. The contact lenses were characterized by studying their optical and physical properties to determine their suitability as extended wear contact lenses. HA-laden hydrogel contact lenses prepared by soaking method showed release up to 48 h with acceptable physical and optical properties. Hydrogel contact lenses prepared by direct entrapment method showed significant sustained release in comparison to soaking method. HA entrapped in hydrogels resulted in reduction in % transmittance, sodium ion permeability and surface contact angle, while increase in % swelling. The impact on each of these properties was proportional to HA loading. The batch with 200-μg HA loading showed all acceptable values (parameters) for contact lens use. Results of cytotoxicity study indicated the safety of hydrogel contact lenses. In vivo pharmacokinetics studies in rabbit tear fluid showed dramatic increase in HA mean residence time and area under the curve with lenses in comparison to eye drop treatment. The study demonstrates the promising potential of delivering HA through contact lenses for the treatment of dry eye syndrome.

Enhanced selective adsorption of cation organic dyes on polyvinyl alcohol/agar/maltodextrin water‐resistance biomembrane

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Effect of contact lenses on ocular biometric measurements based on swept-source optical coherence tomography

“…International practice guidelines recommend at least 3 days of contact lens rest before measurement of biometric parameters. In some circumstances, however, patients may wear contact therapeutic or bandage contact lenses, extended-wear contact lenses, or contact lenses used for ocular drug delivery (i.e., dry eye, glaucoma therapy) during this examination (4)(5)(6)(7)(8) . The effects of contact lens on the reliability of the optical instrument during ocular biometric measurements is of great interest.…”

Approaches in Topical Ocular Drug Delivery and Developments in the Use of Contact Lenses As drug-delivery Devices

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