s Grewia asiatica Mucilage: A Smart Gelling Polymeric Material for Pharmaceutical Applications In Vitro Studies

Background: Natural plant-based materials have several advantages. They are biodegradable, biocompatible, non-toxic, cost-effective, environment friendly, easily available, and can undergo chemical modification. Objective: Grewia asiatica extracts contain various phytoconstituents and have therapeutic benefits such as antimicrobial and anti-diabetic properties. They form colloidal dispersions and make a highly viscous gel in water. Considering these properties of Grewia asiatica mucilage, the present work was aimed to investigate its application in the formulation of gel for the topical delivery of diclofenac sodium. Methods: Gel formulations were prepared with and without penetration enhancers using 1% w/w diclofenac sodium as a model drug. The formulations were subjected to different evaluation tests like physical characterization, pH, spreadability, skin irritation, gel retrogradation, drug content and in vitro drug diffusion. The in vitro diffusion of the drug from different formulations was compared with the in vitro drug release profile of the marketed formulation (Omni gel, Cipla, India). To assess the release mechanism, the in vitro release data was analyzed using Korsmeyers-Peppas’ equation. Results: The mucilage showed good gelling behavior in 5.50, 5.75, 6.00, 6.25 and 6.50% concentrations. All the formulations followed the anomalous transport mechanism of drug release. The formulation BP3 showed 90% of drug release after 5.2h of dissolution study, which was similar to the marketed formulation. Hence, formulation BP3 was ideal among all the formulations. Conclusion: It might be concluded that, the Grewia asiatica mucilage may be used as a natural polymeric material for gel formulation.