Formulation And Evaluation Of Gastro-Retentive Oral Floatable In-Situ Gel Of Ranolazine For Sustained Drug Release

Mayuri Papalal Pol^1*, Ankit Singh², Dhananjay M. Patil³

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ABSTRACT

The present study aimed to develop and evaluate a gastro-retentive oral floatable in-situ gel formulation of Ranolazine for sustained drug delivery and improved bioavailability. In-situ gel systems remain in liquid form before administration and undergo sol-to-gel transition in the gastric environment, thereby enhancing gastric retention and providing controlled drug release. In this study, pectin and HPMC K4M were used as primary polymers to formulate nine batches (F1–F9) of Ranolazine in-situ gel using the ion-activated gelation method. Sodium citrate and calcium chloride were incorporated to regulate gelation behavior and provide ionic cross-linking. All formulations were evaluated for physicochemical parameters including physical appearance, pH, viscosity, in-vitro gelation, floating behavior, drug content, water uptake, and in-vitro drug release. The results indicated that increasing polymer concentration significantly influenced viscosity, gel strength, floating duration, and drug release characteristics. Among all batches, formulation F8 demonstrated optimal performance with suitable pH (8.60 ± 0.01), high viscosity (20768 ± 50 cP), rapid gelation (+++), prolonged floating time (14 hours), and maximum drug content (98.00 ± 0.18%). The formulation exhibited sustained drug release, achieving 99.78% cumulative release within 9 hours. Release kinetic analysis revealed that drug release followed the Korsmeyer–Peppas model, indicating anomalous transport mechanisms. Stability studies performed for three months showed no significant changes in physicochemical properties or drug release behavior. In-vivo pharmacokinetic evaluation in rabbits demonstrated enhanced bioavailability of the optimized formulation, with higher AUC (1764.08 ng·h/ml) and prolonged T_max (6 h) compared to the reference product. The findings confirm that the optimized gastro-retentive in-situ gel formulation of Ranolazine provides sustained drug release, prolonged gastric retention, and improved systemic exposure, making it a promising approach for effective oral drug delivery.

Keywords: Ranolazine, In-situ gel, Gastro-retentive drug delivery, Oral floatable system, Sustained release, Pectin, HPMC K4M, Pharmacokinetics.

How to cite this article: Pol MP, Singh A, Patil DM. Formulation and Evaluation of Gastro-Retentive Oral Floatable In-Situ Gel of Ranolazine for Sustained Drug Release. Int J Drug Deliv Technol. 2026;16(11s): 937-947. DOI: 10.25258/ijddt.16.11s.94

Source of support: Nil.

Conflict of interest: None