高效液相色谱-电感耦合等离子体质谱法测定烟草中砷的形态  

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

作　　者：李莉[1] 李伟青[1] 申德省[1,2] 崔维刚[1] 储晓刚[1] 张峰[1] 

机构地区：[1]中国检验检疫科学研究院烟草安全与控烟技术研究所,北京100123 [2]浙江工商大学食品与生物工程学院,浙江杭州310012

出　　处：《分析测试学报》2013年第8期941-946,共6页Journal of Instrumental Analysis

基　　金：质检公益性行业科研项目(201310134);中央级公益性科研院所基本科研业务费专项(2012JK031)

摘　　要：应用高效液相色谱-电感耦合等离子体质谱联用技术(HPLC-ICP-MS)建立了烟草中As(Ⅲ)、As(V)、一甲基砷酸(MMA)和二甲基砷酸(DMA)4种砷形态的检测方法。研究了不同提取液、提取液体积以及提取时间对提取效果的影响,并对色谱条件进行优化。以15 mL甲醇-水(1∶1)混合液为提取液,30℃超声提取20 min,以(NH4)2HPO4(pH 6.0)为流动相,采用PRP-X100阴离子交换柱对砷形态进行分离。在0.1～25μg/L质量浓度范围内,4种砷形态的线性系数均不小于0.997,日内(n=5)和日间(n=3)RSD均不大于4.2%,仪器检出限为0.1～0.2μg/L,定量下限为0.2～0.5μg/L。在低、中、高3个加标水平下,砷的回收率均为83%～115%,方法稳定性较好,RSD不大于5.7%。采用该方法对国内外8种烟草中的4种砷形态含量进行分析,其含量从高到低依次为As(Ⅴ)、MMA、As(Ⅲ)和DMA。该方法准确、灵敏、方便,适用于烟草中砷形态的测定。A high performance liquid chromatography - inductively coupled plasma mass spectrome tric（ HPLC -ICP- MS） method was developed for the determination of 4 arsenic species, including arsenite （ As （llI ） ）, arsenate （ As （ V ） ）, 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 tobac co samples were mechanically extracted with 15 mL mixture of methanol - water（ 1 ： 1 ） by ultrasonic method for 20 min at 30℃. 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 μg/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 ttg/L and 0. 2 μg/L, and the limits of quantitation （LOQs） were between 0. 2 μg/L and 0. 5 μg/L. The spiked recoveries for all arsenic species were in the range of 83% - 115%. Good sta bilities were found with RSDs not more than 5.7%. The method was applied in the detection of 4 arse nic species in eight kinds of tobaccos, in which all arsenic species were detected and their contents from high to low were ： As （V）, MMA, As （111） and DMA. The method was proved to be accurate, sensitive and convenient for analysis of arsenic species in tobacco sample.

关 键 词：高效液相色谱-电感耦合等离子体质谱 砷形态分析 烟草 

分 类 号：O657.63[理学—分析化学] O613.63[理学—化学]