Comparison of LC-MS, LC-CAD and indirect CE as the assay technique for a non-chromophoric impurity in an active pharmaceutical ingredient

摘要

All three methods meet the requirements of specificity, dynamic range, precision, and accuracy; the indirect CE method did not meet sensitivity requirement. From practical consideration, the LC-CAD method is the best candidate for assay of impurity R in late stage development and beyond commercialization. Further work will be done to evaluate the intermediate precision of the LC-MS and LC-CAD method.