高效液相色谱-电感耦合等离子体质谱联用测定沉积物中不同形态的砷  

Speciation Analysis of Arsenic in Sediment by HPLC-ICP-MS

作　　者：赵彤 陈翠红[1] Zhao Tong;Chen Cuihong(College of Environmental Science and Engineering,Key Laboratory of Pollution Process and Environmental Criteria(Ministry of Education),Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation,Nankai University,Tianjin 300350,China)

机构地区：[1]南开大学环境科学与工程学院,教育部环境污染过程与基准重点实验室,天津市城市环境污染诊断与修复技术工程中心,天津300351

出　　处：《南开大学学报（自然科学版）》2020年第3期97-101,共5页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：天津市自然科学基金(17JCQNJC08400)。

摘　　要：建立了同时从沉积物中提取亚砷酸盐As(Ⅲ)、砷酸盐As(Ⅴ)、一甲基砷酸(MMA)和二甲基砷酸(DMA)4种砷形态的提取方法以及HPLC-ICP-MS联用测定沉积物中4种砷形态化合物的检测方法.探讨了磷酸、抗坏血酸、水浴时间等前处理条件,以及C8色谱柱和Hamilton PRP-X100色谱柱的色谱分离条件,由此建立了沉积物中砷形态的检测方法.结果表明,在95℃条件下水浴60 min,提取剂选择0.3 mol/L磷酸和0.5 mol/L抗坏血酸的混合溶液,4种砷形态化合物加标回收率在70%-110%之间,相对标准偏差(RSD)小于6%.选用Hamilton PRP-X100(5μm×15 cm)色谱柱进行4种砷形态的分离,以15 mmol/L磷酸氢二铵溶液(用甲酸调节pH=6.0)为流动相,在7 min内同时分析检测4种砷形态化合物,As(Ⅲ)、DMA、MMA和As(Ⅴ)的检出限依次为0.22、0.60、0.28和0.78μg/L.该方法实现了对沉积物中常见的不同形态砷的同时分析,具有灵敏度高、精密度好的特点.A method for determining arsenite(As(Ⅲ)),arsenate(As(Ⅴ)),monomethyl arsenic acid(MMA)and dimethyl arsenic acid(DMA)in the sediment by water bath extraction and HPLC-ICP-MS is established.The pretreatment conditions were compared such as phosphoric acid,ascorbic acid,and water bath time,as well as the chromatographic separation conditions of the C8 column and the Hamilton PRPX100 column,thereby a method for detecting the speciation of arsenic in the sediment was established.A mixed solution of 0.3 mol/L phosphoric acid and 0.5 mol/L ascorbic acid was selected as the extractant,and the samples were bathed at 95℃for 60 min.The results show that the recoveries were between 70%and 110%,and the relative standard deviation was less than 6%.Four speciations of arsenic were separated by Hamilton PRP-X100 column.The mobile phase was 15 mmol/L(NH4)2HPO4 solution(adjusted the pH to 6.0 with formic acid).The peaks of four speciations of arsenic appeared within 7 min.The detection limits of As(Ⅲ),DMA,MMA and As(Ⅴ)were 0.22,0.60,0.28 and 0.78μg/L,respectively.The method realizes simultaneous analysis of different speciations of arsenic commonly found in sediments,with high sensitivity and good precision.

关 键 词：高效液相色谱-电感耦合等离子体质谱联用 沉积物 砷形态 

分 类 号：O657[理学—分析化学]