Determination of halogenated compounds with supercritical fluid chromatography–microwave-induced plasma mass spectrometry

Abstract

Helium microwave-induced plasma mass spectrometry (MIP-MS) has been evaluated as an element selective detector for supercritical fluid chromatography (SFC). In this study the determination of halogenated hydrocarbons at trace levels is demonstrated by using two test compounds, 1-chloronaphthalene and 1-bromo-2-methylnaphthalene. The SFC–MIP-MS interface was developed and optimized. Chromatograms obtained for the two halogenated compounds show detection levels in the low picogram range with absolute minimum detectable quantities of 100 and 25 pg for Cl and Br, respectively. Absolute detection limits were found to be 15 pg for Cl and 0.75 pg for Br. The linear ranges are over 3 orders of magnitude (50 pg–50 ng) and reproducibilities for the sample injections are of the order of 5% relative standard deviation. A preliminary chromatogram for a standard pesticide mixture is also presented.