Volume : 13, Issue : 06, June – 2026
Title:
IN SITU GELLING DRUG DELIVERY SYSTEMS: MECHANISMS, POLYMERS, EVALUATION AND PHARMACEUTICAL APPLICATIONS – A COMPREHENSIVE REVIEW
Authors :
Vinay Tripathi, Prashant Maithil, Satkar Prasad
Abstract :
In situ gel systems have emerged as a promising and innovative approach in controlled and sustained drug delivery. These systems are administered as liquids and undergo a phase transition from sol to gel under physiological conditions such as changes in temperature, pH, ionic concentration, or enzymatic activity. The unique sol-to-gel transformation enhances drug residence time, improves bioavailability, reduces dosing frequency, and increases patient compliance. Various natural and synthetic polymers, including pectin, gellan gum, alginic acid, chitosan, xanthan gum, guar gum, carbopol, hydroxypropyl methylcellulose (HPMC), xyloglucan, and poloxamers, have been extensively employed in the development of in situ gelling formulations. Depending on the triggering mechanism, in situ gels may be classified as temperature-sensitive, pH-sensitive, ion-activated, enzymatically cross-linked, or photo-polymerized systems. These formulations have found wide applications in oral, ocular, nasal, rectal, vaginal, injectable, dermal, and transdermal drug delivery. In situ gel systems offer several advantages over conventional dosage forms, including prolonged drug release, enhanced therapeutic efficacy, improved stability, reduced systemic side effects, and better patient acceptability. The present review highlights the mechanisms of in situ gelation, various polymers used in formulation development, applications in different routes of administration, and important evaluation parameters. Owing to their versatility, biocompatibility, and effectiveness, in situ gels represent a promising platform for future controlled drug delivery systems.
Keywords: In Situ Gel, Sol-Gel Transition, Controlled Drug Delivery, Sustained Release, Thermosensitive Gel, Gellan Gum, Carbopol, Chitosan, HPMC, Poloxamer, Ocular Drug Delivery.
Cite This Article:
Please cite this article in press Vinay Tripathi et al., In Situ Gelling Drug Delivery Systems: Mechanisms, Polymers, Evaluation And Pharmaceutical Applications – A Comprehensive Review, Indo Am. J. P. Sci, 2026; 13(06).
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