Formulation and Evaluation of Metformin Hydrochloride Microparticles by Emulsion Solvent Evaporation Technique

Metformin Microparticles of metformin hydrochloride using ethyl cellulose polymer were prepared by Ethyl cellulose the emulsion solvent evaporation technique. The drug polymer ratio and processing Microparticles parameters involved in the preparation of the microparticles were optimized using the Solvent evaporation parameters like particle size, surface morphology, drug content and entrapment efficiency. Optimization Preliminary formulation showed that tween 80 and PVA were important for the formation of small and uniform sized microparticles at concentrations of 0.1% and 1% respectively. Optimization of drug and polymer ratio using ethyl cellulose concentration shows that. 1:1 ratio resulted in uniform microparticles ranging between 600-700 µm and the surface morphology showed smooth spherical shaped particles having micropores. The optimization of process parameters studied by varying the concentration of the ethyl cellulose solution and stirring speed showed that concentrated polymer solution at higher stirring speed helped to get microparticles sized 400-500 microns with high encapsulating efficiency of 97% of metformin hydrochloride.