Experimental Investigation on Efficacy of Eudragit RS 100 Polymer in Prolonging Glibenclamide Release by Intragastric Floating Microsphere Formulation and Physicochemical Evaluation

Abstract

Background: The amalgamation of targeted transportation and enhancement of the release profile of the active pharmaceutical ingredient is a contemporary trend in the evolution of oral medicinal products. A renowned method to actualize this concept is to develop floating gastroretentive delivery systems that ensure an extended stay of the dosage form on the gastric surface. The success of drug delivery is largely dependent on the type of polymer used that sustains the release and avoids any toxic effects. Intragastric floating drug delivery systems are designed to remain buoyant in the stomach without affecting the gastric emptying rate for a prolonged period. This allows for a slow release of the drug in the stomach, which can be particularly beneficial for drugs with a narrow absorption window, like Glibenclamide, an anti-diabetic medication. Objective: The current research focused on the sustained drug delivery of Glibenclamide as intragastric floating microspheres. The goal was to adjust the floatation and drug release pattern using Eudragit RS 100 and magnesium stearate as a droplet stabilizer. Different batches of floating microspheres were optimized based on the polymer, drug-polymer concentration, and the amount of magnesium stearate. The strategy aimed to enhance the effectiveness of Glibenclamide, particularly for individuals with diabetes, by facilitating a controlled and consistent release of the drug in the gastric environment. Materials and Methods: The solvent evaporation method was used to create four batches of intragastric microspheres. The maximum absorbance of the drug, also known as lambda max, was observed at 212 nm. The prepared batches were evaluated for various in-vitro physicochemical parameters. The average particle size was found to be 619 nm. Rheological studies indicated excellent flow properties. The microspheres exhibited in-vitro buoyancy for up to 7 hours. Results: The entrapment efficiency was as high as 93.19%. Scanning Electron Microscopy (SEM) analysis revealed that the microspheres have a porous structure, which allows for the easy movement of solvents and solutes into and out of the microspheres. Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) indicated the physical and chemical properties of the microspheres. All in-vitro drug release and kinetic studies for the optimized batch (F-M4) revealed that Eudragit RS 100 effectively sustained the intragastric delivery of Glibenclamide. Conclusion: Floating drug delivery systems enhance oral dosage forms and the range of APIs by ensuring targeted gastric delivery and modified release. This improves bioavailability, reduces drug losses, and partially mitigates side effects.