HPLC method for estimation of metformin hydrochloride in formulated microspheres and tablet dosage form

A simple, accurate, economical and reproducible HPLC method has been developed for quantitative estimation of metformin hydrochloride from tablet dosage form and formulated microspheres. The developed HPLC method is a reverse phase chromatographic method using phenomenex C(18) column and acetonitrile:phosphate buffer (65:35) pH adjusted to 5.75 with o-phosphoric acid as mobile phase and glipizide as internal standard. The linearity was observed in concentration range of 0-25 mug/ml for metformin hydrochloride. Results of analysis were validated statistically and by recovery studies.