Stable Carbon and Oxygen Isotopic Analysis of Atmospheric Carbon Monoxide Using Continuous-Flow Isotope Ratio MS by Isotope Ratio Monitoring of CO

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• 作者：Urumu Tsunogai ; Fumiko Nakagawa ; Daisuke D. Komatsu ; and Toshitaka Gamo
• 刊名：Analytical Chemistry
• 出版年：2002
• 出版时间：November 15, 2002
• 年：2002
• 卷：74
• 期：22
• 页码：5695 - 5700
• 全文大小：115K
• 年卷期：v.74,no.22(November 15, 2002)
• ISSN：1520-6882

文摘

We have developed a rapid and simple measurementsystem for both content and stable isotopic compositions(¹³C and ¹⁸O) of atmospheric CO, using continuous-flowisotope ratio mass spectrometry by simultaneously monitoring the CO⁺ ion currents at masses 28, 29, and 30.The analytical system consisted sequentially of a sampletrapping port (liquid nitrogen temperature silica gel andmolecular sieve 5A), a gas dryer, a CO purification column(molecular sieve 5A), a cryofocusing unit, and a finalpurification column using a GC capillary. Analytical precision of 0.2” for ¹³C and 0.4” for ¹⁸O can be realizedfor samples that contain as little as 300 pmol of CO within40 min for one sample analysis. Analytical blanks associated with the method are less than 1 pmol. The extent ofanalytical error in ¹³C due to mass-independent fractionation of oxygen in natural CO is estimated to be lessthan 0.3”. Based on this system, we report herein akinetic isotopic effect during CO consumption in soil.