Development and Validation of a Reverse Phase Ultra Performance Liquid Chromatographic Method for Simultaneous Estimation of Nebivolol and Valsartan in Pharmaceutical Capsule Formulation

The present study describes the development and validation of sensitive, novel Ultra Performance Liquid Chromatographic technique to simultaneously evaluate Nebivolol and Valsartan in commercial pharmaceutical capsule formulation. The technique was performed utilizing thermo C18 (4.6 mm×50 mm, 1.9 μm) column having a mobile phase comprising of 10 mM ammonium dihydrogen phosphate pH adjusted to 3.00 ± 0.02 with dilute orthophosphoric acid as buffer, with a ratio of buffer: acetonitrile 60:40 (v/v) and with a flow rate of 0.4 mL min-1. The eluted components were monitored out at 220 nm utilizing a photo diode array detector. The retention times for NBL and VST were 0.48 and 0.83 min respectively. The developed Ultra Performance Liquid Chromatographic method was validated according to ICH guidelines to confirm specificity, linearity, accuracy and precision. The homoscedasticity of the variances and lack of fit in the evaluation of linearity was established using the Cochran’s C test and F-test respectively. The repeatability variances and time different intermediate variances were assessed simultaneously. The time different variances expressed as percentage relative standard deviations (%RSD) and accuracy were well within the limits as prescribed by ICH. In order to designate suitability in the experimental design approach, a robustness test was carried out. To assess robustness 3 aspects were taken into consideration, namely, proportion of flow rate, proportion of acetonitrile in mobile phase and pH; all the three factors have no significant effect on response (assay). Experimental design based robustness with the aid of Full Factorial design (FFD) provided an effective way to simultaneously asses Nebivolol and Valsartan. This method was successfully used to analyze fixed dose capsule samples of Nebivolol as well as Valsartan and can be utilized for regular lab investigation of Nebivolol and Valsartan in capsules.