Pharmacokinetic studies of metformin and glibenclamide in normal human volunteers

ABSTRACT

The study was aimed to evaluate various pharmacokinetic parameters of a commercially available fixed dose combination of oral antidiabetics [Metformin/Glibenclamide 500/5mg tablets] in plasma sample of normal healthy adult male volunteers by applying an accurate, selective, and reproducible HPLC-UV analytical method for quantification of Metformin HCL and Glibenclamide simultaneously in a single chromatographic run. Previously no HPLC-UV analytical method for simultaneous estimation of Metformin/Glibenclamide has been reported in Pakistan. The human plasma samples were evaluated by using an isocratic High Performance Liquid Chromatography [HPLC] system of Sykam consisted of a pump with a column of Thermo Electron Corporation USA [ODS hypersil C[18] 4.6 mm x 250 mm], a UV-detector with data processing Clarity software. The mobile phase of 0.040M Potassium dihydrogen phosphate containing 0.25mL/L triethylamine at pH 3.5 [adjusted with 11 phosphoric acid] and acetonitrile [465 535v/v] was delivered with injection volume of 100microL at flow rate of 1 mL/min at 25degreeC temperature. The detection was performed at lamda[max]230 nm. By applying this method, important pharmacokinetic parameters C[max], T[max], AUC[0-infinity], AUMC[0-infinity], t[1/2], Ke, MRT, V[d] and Cl[T] are calculated. Maximum plasma concentrations C[max] was 131.856 +/- 8.050ng/ml for Glibenclamide [Mean +/- SEM] and 511.106 +/- 12.675 ng/ml for Metformin HCl [Mean +/- SEM].