Compound-Specific Hydrogen Isotope Analysis of Heteroatom-Bearing Compounds via Gas Chromatography鈥揅hromium-Based High-Temperature Conversion (Cr/HTC)鈥揑sotope Ratio Mass Spectrometry

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• 作者：Julian Renpenning ; Steffen K眉mmel ; Kristina L. Hitzfeld ; Arndt Schimmelmann ; Matthias Gehre
• 刊名：Analytical Chemistry
• 出版年：2015
• 出版时间：September 15, 2015
• 年：2015
• 卷：87
• 期：18
• 页码：9443-9450
• 全文大小：365K
• ISSN：1520-6882

文摘

The traditional high-temperature conversion (HTC) approach toward compound-specific stable isotope analysis (CSIA) of hydrogen for heteroatom-bearing (i.e., N, Cl, S) compounds has been afflicted by fractionation bias due to formation of byproducts HCN, HCl, and H₂S. This study presents a chromium-based high-temperature conversion (Cr/HTC) approach for organic compounds containing nitrogen, chlorine, and sulfur. Following peak separation along a gas chromatographic (GC) column, the use of thermally stable ceramic Cr/HTC reactors at 1100鈥?500 掳C and chemical sequestration of N, Cl, and S by chromium result in quantitative conversion of compound-specific organic hydrogen to H₂ analyte gas. The overall hydrogen isotope analysis via GC鈥揅r/HTC鈥搃sotope ratio mass spectrometry (IRMS) achieved a precision of better than 卤 5 mUr along the VSMOW-SLAP scale. The accuracy of GC鈥揅r/HTC鈥揑RMS was validated with organic reference materials (RM) in comparison with online EA鈥揅r/HTC鈥揑RMS and offline dual-inlet IRMS. The utility and reliability of the GC鈥揅r/HTC鈥揑RMS system were documented during the routine measurement of more than 500 heteroatom-bearing organic samples spanning a 未²H range of 鈭?81 mUr to 629 mUr.