Quantification of Genotoxic Impurities by HPLC in Active Pharmaceutical Ingredient Lorazepam

A simple and selective reversed-phase high performance liquid chromatography method was developed and validated for the quantification of 4-chloroaniline, 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide in lorazepam. 4-Chloroaniline is used as a raw material and 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide are formed as intermediates in the synthesis of anxiety disorder active pharmaceutical ingredient lorazepam. This method provided excellent sensitivity and a typical target analyte level of 150 ppm. This method was developed on an Agilent poroshell 120 EC-C18 (100 x 4.6 mm, 4 mu m) column and a photo diode array detector. The proposed method is specific, linear, accurate and precise. The calibration curve was linear over the concentration range of LOQ to 120% with a correlation coefficient of 0.99. This method has low limits of detection and quantification for all the analytes. Accuracy was observed within the range of 85-115% for all the analytes. The developed method was validated as per the ICH guidelines in terms of specificity, precision, limit of detection, limit of quantification, linearity range and accuracy.

Automated summary

A simple and selective reversed-phase high performance liquid chromatography method was developed and validated for the quantification of 4-chloroaniline, 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide in lorazepam. The method provided excellent sensitivity and a typical target analyte level of 150 ppm. It was specific, linear, accurate and precise, with low limits of detection and quantification for all the analytes. This method was validated according to the ICH guidelines.