In situ Gel: A Promising Ocular Drug Delivery System

Abstract

The eye is a vital organ, faces challenges in drug delivery with traditional ophthalmic formulations due to the rapid loss of medications before reaching the cornea. This review explores novel drug delivery systems for ocular administration, emphasizing innovative dosage forms, i.e., in situ gels. This system aims to prolong drug contact time in the eyes, overcoming bioavailability issues associated with conventional delivery methods. The article further delves into in situ gelation approaches, highlighting pH-triggered, temperature-dependent, and ion-activated systems. It explores the use of excipients like polymers and solubilizing agents in the preparation of in-situ gels. The frequently used polymers and their applications in ocular drug delivery are detailed. Studies on the incorporation of nanoparticles in this gelling system for ocular drug delivery. Methodologies for evaluating in situ gels, including pH determination, rheological studies, drug content analysis, in vitro gelation, accelerated stability studies, and FTIR analysis, are presented. The advantages & applications of in situ gels are discussed, along with its limitations. The review concludes by emphasizing the benefits of novel ocular drug delivery systems, particularly in situ ophthalmic systems, which offer controlled and sustained drug release, and the future perspective of in situ gel. These advancements hold promise for more effective therapeutic outcomes in the field of ocular drug delivery.