Nanosemiconductor-Based Photocatalytic Vapor Generation Systems for Subsequent Selenium Determination and Speciation with Atomic Fluorescence Spectrometry and Inductively Coupled Plasma Mass Spectrometry
Nanosemiconductor-Based Photocatalytic Vapor Generation Systems for Subsequent Selenium Determination and Speciation with Atomic Fluorescence Spectrometry and Inductively Coupled Plasma Mass Spectrometry
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基于纳米半导体的光催化蒸汽发生系统，用于利用原子荧光光谱法和电感耦合等离子体质谱法进行后续硒测定和形态形成
DOI：
10.1021/ac3001995
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发表时间：
2012-03-20
影响因子：
7.4
通讯作者：
Wang, Qiuquan
中科院分区：
文献类型：
--
作者：
Li, Huamin;Luo, Yacui;Wang, Qiuquan
我们首次报道了新型的Ag-TiO 2和ZrO 2光催化蒸气发生（PCVG）体系作为有效的进样技术，进一步提高了原子光谱法测定硒的灵敏度，其中导带电子作为“还原剂”，将包括Se-VI在内的硒物种还原并直接转化为挥发性的H2Se，其易于从样品基质中分离并更有效地进行随后的雾化和/或电离。这两个PCVG系统帮助我们克服了在最常规的KBH_4/OH-H ~+系统中遇到的问题，即Se-VI在没有预还原程序的帮助下很难转化为挥发性硒物种。四种最典型的Se-IV、Se-VI、硒代胱氨酸（SeCys）（2）和硒代蛋氨酸（SeMet）物质的检测限（LOD）（3 σ）在UV/Ag-TiO 2-HCOOH中分别降至1.2、1.8、7.4和0.9 ng mL（-1），在UV/Ag-TiO 2-HCOOH中分别降至0.7、1.0、4.2、1.0、1.0和1.0 ng mL（-1）。在UV/ZrO_2-HCOOH介质中，流动注射原子荧光光谱法（AFS）测定的相对标准偏差（RSD）小于5.1%（n = 9，1 μ g·mL ~（-1））。当使用电感耦合等离子体质谱法（ICPMS）时，它们在UV/Ag-TiO 2-HCOOH中达到10、14、18和8 pg mL（-1），在UV/ZrO 2-HCOOH中达到6、7、10和5 pg mL（-1），RSD低于4.4%（n = 9，10 ng mL（-1））。采用GBW（E）080395和SELM-1标准物质对PCVG系统进行了验证，并将其应用于富硒酵母样品中总硒的测定，同时将其作为高效液相色谱（HPLC）与原子荧光光谱（AFS）或电感耦合等离子体质谱（ICPMS）之间的接口，用于富硒酵母水和/或酶提取组分中硒的形态分析。
We reported novel Ag-TiO2- and ZrO2-based photocatalytic vapor generation (PCVG) systems as effective sample introduction techniques for further improving the sensitivity of the atomic spectrometric determination of selenium for the first time, in which the conduction band electron served as a "reductant" to reduce selenium species including Se-VI and convert them directly into volatile H2Se, which was easily separated from the sample matrix and underwent more effectively subsequent atomization and/or ionization. These two PCVG systems helped us to overcome the problem encountered in the most conventional KBH4/OH--H+ system, in that Se-VI was hardly converted into volatile selenium species without the aid of prereduction procedures. The limits of detection (LODs) (3 sigma) of the four most typical Se-IV, Se-VI, selenocystine ((SeCys)(2)), and selenomethionine (SeMet) species were, respectively, down to 1.2, 1.8, 7.4, and 0.9 ng mL(-1) in UV/Ag-TiO2-HCOOH, and 0.7, 1.0, 4.2, and 0.5 ng mL(-1) in UV/ZrO2-HCOOH with the relative standard deviations (RSDs) lower than 5.1% (n = 9 at 1 mu g mL(-1)) when using atomic fluorescence spectrometry (AFS) under flow injection mode. They reached 10, 14, 18, and 8 pg mL(-1) in UV/Ag-TiO2-HCOOH, and 6, 7, 10, and 5 pg mL(-1) in UV/ZrO2-HCOOH with the RSDs lower than 4.4% (n = 9 at 10 ng mL(-1)) when using inductively coupled plasma mass spectrometry (ICPMS). After the two PCVG systems were validated using certified reference materials GBW(E)080395 and SELM-1, they were applied to determine the total Se in the selenium-enriched yeast sample and used as interfaces between high-performance liquid chromatography (HPLC) and AFS or ICPMS for selenium speciation in the water- and/or enzyme-extractable fractions of the selenium-enriched yeast.