Abstract
This paper focuses on extending drug release duration from contact lenses by incorporating catanionic aggregates. The aggregates consist of a long-chain cationic surfactant, i.e., cetalkonium chloride (CKC), and an oppositely charged anti-inflammatory amphiphilic drug. We studied three non-steroidal anti-inflammatory (NSAID) drugs with different octanol–water partition coefficients; diclofenac sodium (DFNa), flurbiprofen sodium (FBNa), and naproxen sodium (NPNa). Confirmation of catanionic aggregate formation in solution was determined by steady and dynamic shear rheology measurements. We observed the increased viscosity, shear thinning, and viscoelastic behavior characteristic of wormlike micelles; the rheological data are reasonably well described using a Maxwellian fluid model with a single relaxation time. In vitro release experiments demonstrated that the extension in the drug release time is dependent on the ability of a drug to form viscoelastic catanionic aggregates. Such aggregates retard the diffusive transport of drug molecules from the contact lenses. Our study revealed that the release kinetics depends on the CKC concentration and the alkyl chain length of the cationic surfactant. We demonstrated that more hydrophobic drugs such as diclofenac sodium show a more extended release than less hydrophobic drugs such as naproxen sodium.
Highlights
Ocular drug delivery is a challenging research field due to the presence of anatomical and physiological barriers that affect the drug bioavailability following multiple routes of administration, including topical, systemic, and injectable [1]
We report the preparation of aggregates composed of a cationic surfactant and an anionic drug for the purpose of extending drug delivery from poly-hydroxy-ethyl-methacrylate contact lenses
We study non-steroidal anti-inflammatory drugs (NSAIDs), a class of drugs that is used for ocular inflammation and pain relief [39]
Summary
Ocular drug delivery is a challenging research field due to the presence of anatomical and physiological barriers that affect the drug bioavailability following multiple routes of administration, including topical, systemic, and injectable [1]. Most ocular diseases are treated with topical application of eye drops, which account for nearly 90% of the currently accessible marketed formulations [2]. Eye drops are inefficient, suffering from tear drainage, in addition to corneal and sclera barriers. In order to address the limitations of eye drops, researchers have explored the use of therapeutic contact lenses [5,6]. When contact lenses containing ophthalmic drugs are placed on the eye, the drug diffuses through the lens matrix and enters the post-lens tear film, in which drug molecules have a longer residence time in comparison to eye drops [7]. A major limitation of unmodified contact lenses is that most of the drug is released within the first few hours [8]. A limited number of these approaches have been examined in clinical trials, such as the treatment of ocular allergy with ketotifen [22] and the treatment of glaucoma with timolol and dorzolamide [23]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
