Pretty J R, Blubaugh E A, Caruso J A
Department of Chemistry, University of Cincinnati, Ohio 45221-0172.
Anal Chem. 1993 Dec 1;65(23):3396-403. doi: 10.1021/ac00071a011.
An on-line anodic stripping voltammetry (ASV) flow system, interfaced with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICPMS) detectors, has been used for determination of arsenic(III) and selenium(IV) and for elimination of polyatomic interferences which arise from chloride in sample matrices. Details of the working electrode preparation are discussed. Arsenic signals in ICP-AES were enhanced by as much as 10 times through preconcentration of sample volumes up to 5 mL. Using ICP-AES detection, recoveries for analyte spikes in 1:10 diluted urine were 102% for As(III) (matrix-matched standards) and 91% for Se(IV) (standards in electrolyte). Using ICPMS detection, determination of certified Se(IV) and Se(IV) spikes in diluted NIST SRM 2670 elevated urine gave recoveries of 92-103%, while recoveries of As(III) spikes in diluted NIST SRM 2670 urine ranged from 94 to 113%. High levels of chloride matrix exhibited little effect on the arsenic signal with ICP-AES or ICPMS detection. Elimination of the polyatomic interference ArCl+ in ICPMS was very efficient for diluted NIST SRM 2670 urine and for a synthetic matrix of 1000 micrograms/mL chloride.
一种与电感耦合等离子体原子发射光谱仪（ICP - AES）和电感耦合等离子体质谱仪（ICPMS）检测器联用的在线阳极溶出伏安法（ASV）流动系统，已用于测定砷（III）和硒（IV），并消除样品基质中氯离子产生的多原子干扰。讨论了工作电极制备的细节。通过对高达5 mL的样品体积进行预浓缩，ICP - AES中的砷信号增强了多达10倍。使用ICP - AES检测，在1:10稀释尿液中添加分析物的回收率，对于砷（III）（基质匹配标准品）为102%，对于硒（IV）（电解质中的标准品）为91%。使用ICPMS检测，在稀释的NIST SRM 2670高浓度尿液中测定认证的硒（IV）和添加硒（IV）的回收率为92 - 103%，而在稀释的NIST SRM 2670尿液中添加砷（III）的回收率范围为94%至113%。高浓度的氯离子基质对ICP - AES或ICPMS检测的砷信号影响很小。对于稀释的NIST SRM 2670尿液和1000微克/毫升氯离子的合成基质，ICPMS中多原子干扰ArCl⁺的消除非常有效。
