Simultaneous monitoring of volatile selenium and sulfur species from se accumulating plants (wild type and genetically modified) by GC/MS and GC/ICPMS using solid-phase microextraction for sample introduction
Simultaneous monitoring of volatile selenium and sulfur species from se accumulating plants (wild type and genetically modified) by GC/MS and GC/ICPMS using solid-phase microextraction for sample introduction
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DOI：
10.1021/ac020285t
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发表时间：
2002-11-15
影响因子：
7.4
通讯作者：
Caruso, JA
中科院分区：
文献类型：
--
作者：
Meija, J;Montes-Bayón, M;Caruso, JA
描述了一种测定芥菜幼苗中产生的超痕量挥发性硒的灵敏方法。使用新型市售 GC/ICPMS 接口与固相微萃取相结合是进行这些研究的一种有前景的方法。事实证明，在氩气放电中添加可选气体（O-2 和 N-2）可以提高 Se 和 S 以及 Xe 的灵敏度，Xe 作为痕量污染气体，用于 ICPMS 优化研究。然而，当添加可选气体时，优化参数会有所不同。在最佳条件下，根据 Se 化合物的不同，检测限可达 1 至 10 ppt；挥发性 S 物质的检测限可达 30 至 300 ppt。使用具有类似样品引入的 GC/MS 可以对根据标准品产生的几种未知物种进行表征。该方法几乎可以同时监测几种植物（例如洋葱、大蒜等）顶部空间的 S 和 Se 物种，尽管目前的工作重点是在封闭小瓶中生长并用 Se 处理的芥菜幼苗。检测到二甲基硒化物和二甲基二硒化物是顶部空间中的主要挥发性硒成分。通过 GC/MS 表征，硫物质也以 (2-丙烯基) 异硫氰酸烯丙酯和异硫氰酸 3-丁烯酯的形式存在。
A sensitive method for determining ultratrace volatile Se species produced from Brassica juncea seedlings is described. The use of a new commercially available GC/ICPMS interface in conjunction with solid-phase microextraction is a promising way to perforin these studies. The addition of optional gases (O-2 and N-2) to the argon discharge proved to increase the sensitivity for Se and S as well as for Xe, which as a trace contaminant gas, was used for ICPMS optimization studies. However, the optimization parameters differ when an optional gas is added. In the best conditions, limits of detection ranging from 1 to 10 ppt can be obtained depending on the Se compound and 30 to 300 ppt for the volatile S species. The use of GC/MS with similar sample introduction permits the characterization of several unknown species produced as artifacts from the standards. The method allows the virtually simultaneous monitoring of S and Se species from the headspace of several plants (e.g., onions, garlic, etc.) although the present work is focused on the B. juncea seedlings grown in closed vials and treated with Se. Dimethyl selenide and dimethyl diselenide were detected as the primary volatile Se components in the headspace. Sulfur species also were present as allyl (2-propenyl) isothiocyanate and 3-butenyl isothiocyanate as characterized by GC/MS.