Development and Validation of a Stability-Indicating Liquid Chromatographic Method for Estimating Vilazodone Hydrochloride in Pharmaceutical Dosage Form Using Quality by Design.

A stability-indicating liquid chromatographic method was developed employing the principles of quality by design (QbD) to quantify vilazodone hydrochloride (VLN) in pharmaceutical dosage form. A Box-Behnken experimental design was employed to establish optimum conditions including method robustness by selecting organic phase proportion (%), mobile phase flow rate (mL/min) and pH of buffer as the factors, to study their effect on plate number as the response variable. Chromatography was performed on a C-18 column using methanol:phosphate buffer of pH 7.0 (85:15, v/v) as the mobile phase at a flow rate of 1.2 mL/min with photo diode array (PDA) detection at 285 nm. Calibration curve was linear over 5-80 µg/mL with values of accuracy within 99.4-100.8%. The limit of detection and quantification were found to be 1.5 and 5.0 µg/mL, respectively. The developed method revealed high specificity for VLN and its degradation products formed during forced degradation conditions. Furthermore, control strategies were developed based on system suitability test result. The QbD-based developed liquid chromatographic method was found suitable for routine analysis of VLN in bulk drug and pharmaceutical dosage form.