Verdon Carl P, Caldwell Kathleen L, Fresquez Mark R, Jones Robert L
Inorganic and Radiation Analytical Toxicology Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, N.E., Mail Stop F-50, Atlanta, GA 30341, USA.
Anal Bioanal Chem. 2009 Feb;393(3):939-47. doi: 10.1007/s00216-008-2537-3. Epub 2008 Dec 11.
A robust analytical method has been developed and validated by use of high-performance liquid chromatography inductively coupled plasma mass spectrometry with Dynamic Reaction Cell (DRC) technology that separates seven arsenic (As) species in human urine: arsenobetaine (AB), arsenocholine, trimethylarsine oxide (TMAO), arsenate (As(V)), arsenite (As(III)), monomethylarsonate, and dimethylarsinate. A polymeric anion-exchange (Hamilton PRP X-100) column was used for separation of the species that were detected at m/z 75 by ICP-DRC-MS (PerkinElmer SCIEX ELAN DRCII) using 10% hydrogen-90% argon as the DRC gas. The internal standard (As) is added postcolumn via an external injector with a sample loop. All analyte peaks were baseline-separated except AB and TMAO. Analytical method limits of detection for the various species ranged from 0.4 to 1.7 microg L(-1) as elemental As. As(III) conversion to As(V) was avoided by adjusting the urine sample to <pH 6. Analyses of the National Institute of Standards and Technology standard reference material (SRM) 2670 and 2670a elevated and National Institute for Environmental Studies certified reference material (CRM) no. 18 for arsenic species yielded results within the certified SRM-CRM limits for As species; likewise, the sum of all species compared favorably to SRM 2670 and 2670a target values for total As. This As speciation method is now being used in a production mode for the analysis of a US population survey, the National Health and Nutrition Examination Survey, as well as for other biomonitoring studies of As exposure. This method meets our requirement for sample throughput of 2,000-3,000 sample analyses per year.
已开发并验证了一种强大的分析方法，该方法使用配备动态反应池（DRC）技术的高效液相色谱 - 电感耦合等离子体质谱法，可分离人尿中的七种砷（As）形态：砷甜菜碱（AB）、砷胆碱、三甲基氧化砷（TMAO）、砷酸盐（As(V)）、亚砷酸盐（As(III)）、一甲基砷酸盐和二甲基砷酸盐。使用聚合物阴离子交换（Hamilton PRP X - 100）柱分离这些形态，通过电感耦合等离子体质谱 - 动态反应池（ICP - DRC - MS，PerkinElmer SCIEX ELAN DRCII）在m/z 75处进行检测，使用10%氢气 - 90%氩气作为DRC气体。内标（As）通过带样品环的外部进样器在柱后添加。除AB和TMAO外，所有分析物峰均实现基线分离。各种形态的分析方法检测限以元素As计为0.4至1.7 μg L⁻¹。通过将尿液样品pH值调至<6避免As(III)转化为As(V)。对美国国家标准与技术研究院标准参考物质（SRM）2670和2670a以及日本国立环境研究所认证参考物质（CRM）砷形态标准物质18号的分析结果在认证的SRM - CRM砷形态限值范围内；同样，所有形态的总和与SRM 2670和2670a总砷目标值相比良好。这种砷形态分析方法目前正用于美国人群调查——国家健康与营养检查调查以及其他砷暴露生物监测研究的生产模式分析中。该方法满足我们每年2000 - 3000个样品分析的样品通量要求。
