RP-HPLC Method for Simultaneous Estimation of Escitalopram oxalate and Etizolam in Bulk and Tablet Dosage Form

Present work describes a selective, precise and accurate Reverse Phase High Performance Liquid Chromatographic (RP-HPLC) method for simultaneous estimation of Escitalopram Oxalate (ESC) and Etizolam (ETI) on Kromasil 100 C18, 5µ(150×4.6 mm) Column using Acetonitrile:0.005 M Hexane Sulfonic Acid pH 3.0 (adjusted with o-phosphoric acid) (40:60 v/v) as mobile phase, at a flow rate of 1.0 ml/min and the detection wavelength was 254 nm. The retention time for ESC and ETI was found to be 3.66 and 8.07 min, respectively. The ion-pairing reagent improved the retention of polar ESC on Reverse-phase column. The method was validated for linearity, precision, accuracy, LOD, LOQ robustness, solution stability and specificity. The method was linear in the concentration range of 20-160µg/ml for ESC and 2-16 µg/ml for ETI with a correlation coefficient of 0.9994 and 0.9993 for respective drugs. The percent recovery was found in the range of 98.14-101.72% and 98.83-101.12 % for ESC and ETI, respectively. The specificity of method was established based on peak purity data. The proposed method was successfully applied for quantitative determination of escitalopram oxalate and Etizolam in combined tablet dosage form for routine analysis.