title: Determination of impurities in medical products containing metformin hydrochloride.
abstract: The object of this study was to present a high-performance liquid chromatography (HPLC) method allowing to identify and quantify the impurities in medical products in which the only active substance is metformin hydrochloride. Metformin (dimethylbiguanide) is a biguanide derivative active after oral administration. It reduces the basic and postprandial blood glucose levels in patients with type II diabetes (insulin-independent), with partially maintained insulin secretion. The separation of the impurities was performed using a PARTISPHER SCX column and a spectrophotometric detector (lambda = 218 nm). The mobile phase was 1.7% (w/v) ammonium dihydrogen phosphate water solution, with pH adjusted to 3.1 using 85% orthophosphoric acid. The proposed method is rapid, sensitive and selective, and it can be used to evaluate those medical products for which the impurity tests are not currently performed, as well as those for which only cyanoguanidine or cyanoguanidine and melamine assays are performed.
authors.affiliation: National Medicines Institute, Department of Biochemistry and Biopharmaceuticals, 30/34 Chełmska St., 00-725 Warszawa, Poland. gabriela@klaczkow.pl
authors.forename: Gabriela
authors.initials: G
authors.lastname: Kłaczkow
authors.forename: Elzbieta L
authors.initials: EL
authors.lastname: Anuszewska
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D007004:Hypoglycemic Agents / Q000032:analysis*; D008687:Metformin / Q000032:analysis*; D015203:Reproducibility of Results; D013053:Spectrophotometry
chemical_list: D007004:Hypoglycemic Agents; D008687:Metformin