Abstract

IN SITU GEL: AN INNOVATIVE STRATEGY FOR CONTROLLED AND TARGETED DRUG DELIVERY

Shweta Ambuskar*, Diksha Desai, Pratiksha Salokhe and Omkar Chavan

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Abstract

Conventional drug delivery systems often suffer from limitations such as low bioavailability, poor site specificity, and systemic side effects. In response to these challenges, in situ gel systems have emerged as a promising alternative, offering controlled and sustained drug release through physiological triggers like temperature, pH, and ionic strength. These systems remain in a sol state during administration and undergo gelation upon exposure to specific physiological conditions, enhancing drug residence time and therapeutic efficacy. Various approaches— thermosensitive, pH-sensitive, and ion-activated—have been explored using both natural and synthetic polymers. In situ gels have demonstrated versatility across multiple routes of administration, including ocular, nasal, injectable, vaginal, and buccal delivery, significantly improving patient compliance. Recent advancements incorporating nanocarriers have further enhanced the efficiency of these systems. Despite their potential, challenges such as polymer toxicity and formulation consistency remain. This review discusses the mechanisms, formulation strategies, polymers used, applications, and evaluation parameters of in situ gels, while highlighting current innovations and future research directions in this dynamic field.

Keywords: In situ gel, Floating drug delivery systems (FDDS), Thermosensitive gelation, pH-responsive polymers, Ion-activated systems, Controlled drug release.