A COMPREHENSIVE ION PAIR-FREE CO-ELUTION LIQUID CHROMATOGRAPHY TO DETERMINE THE METFORMIN AND VILDAGLIPTIN, SITAGLIPTIN SIMULTANEOUSLY IN THE PHARMACEUTICAL DOSAGE FORM

Mrunalini D. Kulkarni and Mukesh L. Parab*

ABSTRACT

An ion pair-free, quick equilibrating, swift and selective HPLC (high performance liquid chromatography) method has been developed to determine the oral antidiabetics: Metformin hydrochloride (MT) and its combination formulation along with Sitagliptin phosphate (ST), Vildagliptin(VG) in single drug formulation and combination solid oral dosage formulations. The isocratic elution mode using solvents A- water and triethylamine adjusted to intermediate pH with ortho-phosphoric acid and B-ethanenitrile as a mobile phase at a flow rate of 1.0 mL/min on Waters Sperisorb ODS2, 250 × 4.6 mm, 5μm HPLC column at 35°C temperature. Area responses were found to be linear, and the correlation coefficients for VG, ST and MT are 0.9996, 0.9995 and 0.9998, respectively. The established limit of detection and limit of quantification for VG was 0.22 μg/ml and 0.90μg/ml, 0.18 μg/ml and 0.64μg/ml for ST, and 0.25 μg/ml and 1.04 μg/ml for MT. The recovery of results is between 98.0 and 102.0 percent with a repeatability of ≤2.0 percent. The method is cost-effective, free of ion-pair reagents and applicable for determining the assay of cited drugs in pharmaceutical preparations and their routine quality control.

Keywords: RP-HPLC; Antidiabetic drugs; Metformin hydrochloride; Sitagliptin phosphate; Vildagliptin.