Determination of Arsenic and Its Species in Tobacco by High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

KeyWord:high performance liquid chromatography-inductively coupled plasma-mass spectrometry£¨HPLC-ICP-MS£©  arsenic species  tobacco

Abstract:

      A high performance liquid chromatography-inductively coupled plasma mass spectrometric£¨HPLC-ICP-MS£© method was developed for the determination of 4 arsenic species,including arsenite£¨As£¨¢ó£©£©,arsenate£¨As£¨¢õ£©£©,monomethylarsonic acid£¨MMA£© and dimethylarsinic acid£¨DMA£©,in tobacco.The extract efficiencies of different extract solvents,extract solvent volume and extract time were investigated.The chromatographic conditions were also optimized.The milled tobacco samples were mechanically extracted with 15 mL mixture of methanol-water£¨1¡Ã1£© by ultrasonic method for 20 min at 30 ¡æ.The target species in tobacco were analyzed on an anion exchange cartridge£¨PRP-X100£© using diammonium phosphate£¨pH 6.0£©as mobile phase.Good linearities of 4 arsenic species were observed in the range of 0.1-25 ¦Ìg/L with correlation coefficients not less than 0.997.The RSDs of intra- and inter-day were both not more than 4.2%.The limits of detection£¨LODs£© were between 0.1 ¦Ìg/L and 0.2 ¦Ìg/L, and the limits of quantitation£¨LOQs£© were between 0.2 ¦Ìg/L and 0.5 ¦Ìg/L.The spiked recoveries for all arsenic species were in the range of 83%-115%.Good stabilities were found with RSDs not more than 5.7%.The method was applied in the detection of 4 arsenic species in eight kinds of tobaccos,in which all arsenic species were detected and their contents from high to low were:As£¨¢õ£©,MMA,As£¨¢ó£© and DMA.The method was proved to be accurate,sensitive and convenient for analysis of arsenic species in tobacco sample.