Formulation and Evaluation of Extended Release Metformin Hydrochloride Microspheres by Ionotropic Gelation Technique

Microsphere of metformin hydrochloride were prepared by ionotropic gelation technique using Sodium alginate, Methocel K4M (Hydroxypropylmethylcellulose) and Surelease (Ethyl cellulose). Extended release microsphere of metformin hydrochloride were developed using different drug, polymer and crosslinking agent ratios and the formulation were optimized on the basis of in-vitro drug release. Prepared microspheres were evaluated for particle size, angle of repose, percentage yield, drug entrapment efficiency, IR study, stability study was done. The advance study was on optimizing batch such as Differential scanning calorimetry and scanning electron microscopy. From the results of dissolution data after evaluating by using Korsmeyer's and Peppas equation, the values of diffusion coefficient of all batches was found between 0.5972 to 0.7594, it shows that all the batches gives the release by diffusion followed by Non-Fickian transport mechanism