Hplc Method for the Quantification of Metformin Hydrochloride in Bulk and Dosage Forms

A simple, selective, rapid and economical reversed phase high performance liquid chromatographic method for the determination of metformin hydrochloride in bulk and dosage forms has been developed and validated. The separation was carried out on a Discovery reversed phase C-18 column (250 mm x 4.6 mm, 5.0 μm) with UV detection at 233 nm. The mobile phase contained 34% acetonitrile and 66% aqueous phase. Aqueous phase contained 10 mM KH2PO4 and 10 mM sodium lauryl sulfate. Mobile phase pH was adjusted to 5.2. The mobile phase was run isocratically. The flow rate of the mobile phase was maintained at 1.3 ml/min. The linearity of the calibration curve was obtained in the concentration range of 2.5 to 20 μg ml -1 and coefficient of determination (R 2 ) was found to be 0.9985. The % RSD value for intraday and interday precision was below 1 which indicated that the method was precise. Limit of detection and limit of quantification were 0.1 and 0.3 μg/ml respectively. INTRODUCTION: Metformin hydrochloride (1, 1dimethyl biguanide hydrochloride) is an oral antidiabetic drug 1 . The structural formula is as shown: FIGURE 1: CHEMICAL STRUCTURE OF METFORMIN