短柱分离-电感耦合等离子体质谱联用测定大米和紫菜中的无机砷  

Determination of inorganic arsenic species in rice and laver by liquid chromatography-inductively coupled plsama mass spectrometry with C_8 reversed-phase chromatogram column

作　　者：倪张林[1,2] 汤富彬[1,2] 喻晴[1,2] 莫润宏 

机构地区：[1]中国林业科学研究院亚热带林业研究所 [2]国家林业局经济林产品质量检验检测中心(杭州),富阳311400

出　　处：《分析试验室》2014年第12期1392-1396,共5页Chinese Journal of Analysis Laboratory

基　　金：中央级公益性科研院所基本科研业务费专项资金(RISF2013011);国家林业公益性行业科研专项(201204414)资助

摘　　要：建立了C8反相色谱短柱分离-电感耦合等离子体质谱联用技术（LCICP-M S）测定大米和紫菜中无机砷的检测方法。样品用含有2%H2O2的流动相在1000W大功率超声进行萃取（70℃,50 min）,使其中的无机砷转化为五价砷,以1 mmol/L KH2PO4＋1 mmol/L四丁基氢氧化铵（p H 5.5）为流动相,经C8反相色谱柱分离,电感耦合等离子体质谱仪进行定量分析。方法学验证表明：在0.5-50μg/L范围内无机砷线性良好,线性相关系数（r2）为0.9996,定量限（LOQ）为0.3μg/L,加标回收率在85.2%-109%之间,相对标准偏差（RSD,n=6）在2.1%-4.4%。方法适合于批量测定大米和紫菜样品中的无机砷。A method for the analysis of inorganic arsenic in rice and laver by liquid chromatography- inductively coupled plasma mass spectrometry（ LC- ICP- MS） has been proposed. Rice and laver were extracted by ultrasonic with the power of 1000W（ 70℃,50min）. 1mmol / L potassium dihydrogen phosphate ＋ 1mmol / L tetrabutyl ammonium hydroxide（ TBAOH） with 3% hydrogen peroxide（ V / V） was used as extraction solvent that could convert all forms of inorganic arsenic to pentavalent arsenic in extraction process. The LC separation was performed on a C8reversed- phase chromatographic column utilizing a isocratic elution program with1 mmol / L potassium dihydrogen phosphate（ p H 5. 5） as the mobile phase. Methodology validation showed that linear correlation coefficient（ r） for inorganic arsenic was 0. 9996 at 0. 5 - 50 μg / L and quantitative limit（ LOQ） was 0. 3 μg /L. The recoveries were between 85. 2% and 109% with relative standard deviations（ RSD,n = 6） of 2. 1% - 4. 4%. The method was efficient,reliable and sensitive,which could meet requirement for the determination of inorganic arsenic in rice and laver.

关 键 词：液相色谱-电感耦含等离子体质谱 大米 紫菜 无机砷 

分 类 号：O657.63[理学—分析化学]