Detection of sulfur-containing impurities in pharmaceutical samples by high performance liquid chromatography/chemical reaction interface mass spectrometry

This paper describes the use of chemical reaction interface mass spectrometry (CRIMS) combined with liquid chromatography for the detection of trace level sulfur-containing impurities in pharmaceutical materials. A mixture of sulfur- and non-sulfur-containing compounds were analyzed initially to test the system. Then the determination of trace level impurities in a cimetidine drug substance was carried out. Detection of sulfur-containing impurities at less than 0.1% of the major component was obtained with good linearity. The results obtained are consistent with the expected results for this sample and illustrate the applicability of the technique. Copyright (C) 2001 John Wiley & Sons, Ltd.