Determination of Trace Level Perchlorate in Sludge Samples by Ion Chromatography-Electrospray Tandem Mass Spectrometry

A rapid and highly sensitive method for the determination of trace level perchlorate was set up using ion chromatography-electrospray tandem mass spectrometry (IC/ESI-MS/MS) in the negative electrospray interface (ESI) and the multiple reaction-monitoring (MRM) mode. Using high capacity and hydroxide selective column IonPac AS20, perchlorate was separated by KOH eluent generated from Eluent Generator Cartridge (EGC). The transition of 100.8/84.9, 98.8/66.9 and 100.8/68.9 were monitored for confirmation of the target analyte and 98.8/82.9 for quantifying. The calculated method detection limit of quantitation (S/N = 3) was as good as that of 0.01 μg l−1 for perchlorate. A linear calibration was obtained over the range of 0.05–100 μg l−1 with a correlation coefficient of 0.9988. The relative standard deviation for nine successive injections of 0.2 μg l−1 perchlorate was 2.3%. This method was applied for the detection of trace level perchlorate in sludge samples, which were obtained from different areas in China. The recoveries of spiked standard were 88.5%–102.2%.