Design development and evaluation of controlled release micro-sponge drug delivery system

The present study focuses on the design, development, and evaluation of a controlled release micro-sponge drug delivery system for Nimesulide, aimed at enhancing therapeutic efficacy and reducing dosing frequency. Micro-sponges were prepared using the quasi-emulsion solvent diffusion method, a simple and reproducible technique that enables the formation of porous polymeric microspheres. Ethyl cellulose was employed as the polymer matrix due to its biocompatibility and sustained release properties. Pre-formulation studies confirmed the physicochemical suitability of Nimesulide for micro-sponge encapsulation. A series of formulations (F1 to F5) were developed by varying the drug-to-polymer ratio and evaluated for particle size, production yield, drug content, and encapsulation efficiency. Results indicated that increasing the polymer concentration led to larger particle size and higher yield but decreased drug content. In vitro studies demonstrated that all formulations sustained drug release over 24 hours, with formulation F1 showing the most favorable profile. The micro-sponge system presents a promising alternative to conventional dosage forms, offering controlled release, improved patient compliance, and reduced adverse effects.