Determination of Perchlorate in Drinking Water by Ultra Performance Liquid Chromatography-Electrospray Ion Source Tandem Mass Spectrometry

An ultra performance liquid chromatography-electrospray ion source tandem mass spectrometric(UPLC-ESI MS/MS) method was developed for the determination of perchlorate in drinking water.Compared with ion chromatography,UPLC-ESI MS/MS has the advantages of higher sensitivity,less matrices interference and less relative interference by ionic strength which make it satisfy the demand of determining the content of perchlorate in drinking water.300Extend-C18 was used as the analytical column with the mobile phase of 10% methanol.ESI MS/MS tandem mass spectrometry was used as the detector and the ion-pair m/z 99.5→82.9 was monitored under multiple reaction monitoring(MRM) mode.The method was linear(r2=0.999 9) in the range of 0.2-10 μg/L,and the limit of detection(LOD) of this method was 0.15 μg/L.The average recovery from spiked sample was 82% with relative standard deviation(RSD) of 4.4%.The method was used to determine the concentration of perchlorate in drinking water of some Beijing urban areas.The concentrations of perchlorate in five water samples were detected to be in the range of 0.040-0.262 μg/L.Therefore,it was proved that the content of perchlorate in the drinking water of Beijing was in the range of safe threshold value and it would not threat the health of residents.