Validation of a capillary electrophoresis method for analysis of rabeprazole sodium in a pharmaceutical dosage form

Rabeprazole sodium is an antisecretory agent that inhibits the enzyme H+/K+ ATPase present in the stomach parietal cells. There are few data about its quantitative determinations in laboratorial routines. Capillary electrophoresis is a method being used increasingly for analysis of pharmaceutical compounds, the main advantages of which are the simplicity of instrumentation, low consumption of sample and reagents, and fast analysis. The aim of this study was to develop and validate a capillary electrophoresis method for determination of rabeprazole sodium in coated tablets. The conditions used were a bare fused silica capillary with 48.0 cm length (39.5 cm effective) and 75 microm id; a 10mM, pH 9.0, sodium tetraborate run buffer; a diode array detector set at 291 nm; hydrodynamic injection (50 mbar/5 s); and a voltage of 20 kV. HP Chemstation CE rev. A.06.03 software was used for system control, data acquisition, and analysis. The method was demonstrated to be linear in the concentration range of 5.0-40.0 microg/mL (r = 0.9993), precise (interday relative standard deviation = 0.49), accurate (mean recovery = 103.1%), and specific. The limits of detection and quantitation were 1.29 and 3.91 microg/mL, respectively.