Development and Evaluation of pH-Sensitive Eudragit-Coated Albumin Microparticles for Colon-Targeted Delivery of Vancomycin Hydrochloride

Colon-targeted drug delivery systems are a promising approach for the treatment of colonic diseases while reducing systemic side effects. The present study aimed to develop and evaluate pH-sensitive microparticles of Vancomycin hydrochloride using egg albumin as a biodegradable polymer and Eudragit S-100 as an enteric coating polymer. Microparticles were prepared by the emulsion solvent evaporation technique and subsequently coated to achieve colon-specific release. Drug–polymer compatibility was confirmed by FTIR analysis, indicating no significant interaction. The prepared formulations exhibited satisfactory percentage yield and drug entrapment efficiency, with the optimized formulation showing 97.46% yield and 74.6% entrapment efficiency. Particle size analysis revealed microparticles in the micron range, and zeta potential values indicated good formulation stability. In-vitro drug release studies demonstrated minimal release in gastric and intestinal conditions, followed by a significant increase at colonic pH. The presence of rat caecal contents further enhanced drug release. Stability studies showed minimal reduction in drug entrapment over three months, indicating good stability. Overall, the developed system provides an effective platform for colon-targeted delivery of Vancomycin hydrochloride and may improve therapeutic outcomes in colonic infections.