Development and validation of method for the estimation of aprepitant Form-II in aprepitant drug substance (Mixture of aprepitant Form-I and Form-II) by powder X-Ray diffractometer (PXRD)

A PXRD quantitative method is developed and validated for the estimation of Aprepitant Form-II in Aprepitant Drug substance (mixture of Aprepitant Form-I and Form-II). The PXRD conditions for the Slow scan method developed for the estimation of Aprepitant Form-II at 12.6 with a radiation source of Copper Kα1 ( λ = 1.54060A°). The Angular range was 11.0 to 13.0°2θ with the Voltage and Current set to 40KV and 40mA and a step size of 0.005° along with sample rotation of 30 rpm. The scan type is Locked coupled, continuous with a
high sensitive Lynxeye detector. The developed method was validated for Specificity, Linearity, Precision,
accuracy and Robustness. The PXRD method is Linear with a concentration range of 5% to 90% w/w. with correlation coefficient of 0.999. The recoveries ranged between 89.6% - 103.4% for 10% and 60% levels. The Method was found to be specific, linear, sensitive, precise, accurate and robust for the estimation of Aprepitant Form-II in Aprepitant Drug substance.