Development And Quantification Of Isothiocyanate Impurity In Enzalutamide Drug Substance By Using Rp-Hplc Technique

Abstract

In the routine pharmaceutical industry manufacturing process sometimes few unknown impurities will trigger during its quality assessment practice. Those unknown impurities might be impact on downstream synthesis and which leads to the quality of active pharmaceutical ingredients (API’s). A new, simple, rapid, selective, precise and accurate reverse phase high performance liquid chromatography method has been developed for quantification of isothiocyanate impurity in Enzalutamide drug substance. The separation was achieved by using stationary phase Phenomenex Kinetex (100 x 2.1 mm, 3.5µm) column  and the mobile phase consists of two channels A and B. channel-A: 0.1% formic acid buffer and channel-B: acetonitrile: water (85:15 v/v) in the proportion of gradient elution. The flow rate is 0.5 mL/min. The column temperature was maintained at 40°C and sample cooler temperature was maintained at 5°C, injection volume 5 µL and wavelength 295nm. The retention time of isothiocyanate impurity was noted to be 13.7 min respectively. The limit of detection (LOD) and limit of quantitation (LOQ) for isothiocyanate impurity 0.7492 µg/mL and 2.7372 µg/mL respectively. The Linearity of isothiocyanate impurity was carried out at different concentrations ranging from 2.281-13.686 µg/mL and correlation coefficient was found to be 0.9998. Precision of the method was performed by injecting standard injections, the %RSD value of isothiocyanate impurity was found to be 1.36%. Accuracy was confirmed by recovery studies the %recovery of shown in the range of LOQ and 150% and the results obtained were found to be within the limits. Hence the method was found to be accurate. The method was validated as per ICH guidelines.