Comparison of Capillary Electrophoresis and UV Derivative Spectrophotometry for Determination of Pioglitazone, Glipizide and Repaglinide

Abstract

Two new methods, capillary electrophoresis (CE) and UV derivative spectrophotometry were developed and validated for determination of three oral antidiabetics, pioglitazone, glipizide and repaglinide in pharmaceutical formulations. CE was performed using a 75 µm x 87 cm fused silica capillary (65 cm effective length) and UV detection. The phosphate buffer at pH 8.2, 30 kV voltage, 30°C temperature and hydrodynamic injection (10 mbar, 6 s) were chosen as CE parameters. UV spectrophotometry was carried out using first (D1) and second (D2) derivative spectra obtained by the peak-zero (P-0) and peak-to-peak (P-P) techniques. Precision and accuracy of the both methods were compared. In spite of some statistical differences, the results showed that the both methods are suitable for quantitative determination of these five oral antidiabetics and can be applied for different pharmaceutical purposes.