New Concepts for the Determination of Oxidation Efficiencies in Liquid Chromatography-Isotope Ratio Mass Spectrometry.
New Concepts for the Determination of Oxidation Efficiencies in Liquid Chromatography-Isotope Ratio Mass Spectrometry.
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液相色谱-同位素比质谱测定氧化效率的新概念
DOI：
10.1021/acs.analchem.8b05315
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发表时间：
2019
影响因子：
7.4
通讯作者：
T.C. Schmidt
中科院分区：
文献类型：
--
作者：
D. Köster;Sanchez Villalobos;M.A. Jochmann;W.A. Brand;T.C. Schmidt
在液相色谱-同位素比质谱联用（LC-IRMS）中，分析物在LC系统上分离并连续氧化为CO2，这是测定化合物特定碳同位素比所需的。氧化在在线反应器中通过硫酸根进行。界面中的反应条件取决于通过LC方法确定的流动条件以及在界面中添加的氧化剂和磷酸的流速和浓度。为了确定准确的同位素比，将分析物中所含的碳定量转换为CO2测量气体是先决条件。尽管已知某些分析物难以被硫酸根氧化，但在方法开发期间通常不会评估氧化效率。为了评估LC-IRMS系统的氧化效率，评估了三种不同的方法。(1)测定界面的洗脱液流中的残留有机碳以计算取决于初始分析物浓度的氧化产率。(2)将IRMS响应校准到无机碳参比物质，以在IRMS作为检测器的帮助下确定氧化效率。(3)故意降低氧化温度，同时监测δ 13 C和信号强度。IRMS信号与分析物浓度的线性关系是LC-IRMS中完全氧化的指标的常见假设可能被推翻。所有这三种方法都可以应用于LC-IRMS中的未来方法开发，现有流动注射应用的监测，以及已建立的LC-IRMS方法中完全氧化的验证。
In liquid chromatography coupled to isotope ratio mass spectrometry (LC–IRMS), analytes are separated on an LC system and consecutively oxidized to CO2, which is required for the determination of compound-specific carbon isotope ratios. Oxidation is performed in an online reactor by sulfate radicals. Reaction conditions in the interface depend on the flow conditions determined by the LC method and the flow rates and concentrations of oxidation agent and phosphoric acid added in the interface. To determine accurate isotope ratios, a quantitative conversion of the carbon contained in the analyte to the CO2measurement gas is a prerequisite. Oxidation efficiencies are not commonly evaluated during method development, although certain analytes are known to be difficult to be oxidized by sulfate radicals. For the assessment of the oxidation efficiency of the LC–IRMS system, three different approaches were evaluated. (1) Residual organic carbon in the eluent stream of the interface was determined to calculate oxidation yields depending on the initial analyte concentration. (2) The IRMS response was calibrated to an inorganic carbon reference material to determine oxidation efficiencies with the help of the IRMS as a detector. (3) The oxidation temperature was deliberately reduced while monitoring the δ13C and signal intensity. The common assumption that a linear relation of IRMS signal to analyte concentration is an indicator for complete oxidation in LC–IRMS could be disproved. All three approaches can be applied for future method development in LC–IRMS, monitoring of existing flow injection applications, as well as for verification of complete oxidation in established LC–IRMS methods.
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影响因子：
7.4
作者：
Didier Diomandé;Estelle Martineau;A. Gilbert;Pierrick Nun;Ariaki Murata;Keita Yamada;N. Watanabe;I. Tea;R. Robins;N. Yoshida;G. Remaud
通讯作者：
Didier Diomandé;Estelle Martineau;A. Gilbert;Pierrick Nun;Ariaki Murata;Keita Yamada;N. Watanabe;I. Tea;R. Robins;N. Yoshida;G. Remaud
使用液相色谱-同位素比质谱法对生物蛋白水解产物中的氨基酸进行 delta13C 分析的三相液相色谱方法。
影响因子：
2.9
作者：
Colin Smith;B. Fuller;K. Choy;M. Richards
通讯作者：
M. Richards
通过液相色谱与同位素比质谱联用对小分子和大分子进行同位素比监测。
DOI：
10.1002/rcm.2117
发表时间：
2005
期刊：
Rapid communications in mass spectrometry : RCM
影响因子：
--
作者：
J. Godin;J. Hau;L. Fay;G. Hopfgartner
通讯作者：
G. Hopfgartner
卤代苯甲酸酯的液相色谱/同位素比质谱分析，用于表征 Thauera 氯苯甲酸 CB-1T 中潜在的降解反应
DOI：
10.1002/rcm.8113
发表时间：
2018
期刊：
Rapid communications in mass spectrometry : RCM
影响因子：
--
作者：
Franke S;Kummel S;Nijenhuis I
通讯作者：
Nijenhuis I
通过液体流动注射同位素比质谱法直接分析白蛋白中的碳同位素变异性
影响因子：
3.2
作者：
R. J. Caimi;J. Brenna
通讯作者：
J. Brenna