The Principle and Applications of Gas Chromatograph Isotopic Ratio Mass Spectrometer

摘要

The organic compounds in nature are usually consisted of basic units such as atoms and molecules. The isotope ratio of the composing atom are generally affected by factors including the environment of raw materials (namely, reactants), the reaction pathway (such as manufacturing means, synthetic means, and growth means), weathering sample collection, storage, preparation, treatment, analysis, etc. The resultant ratio is different and varying. Gas chromatograph - isotope ratio mass spectrometer (GC-IRMS) uses GC to separate sample into individual organic compound which is combusted under high temperature (800 - 950℃) in furnace and form CO{sub}2 and H{sub}2O. After the removal of H{sub}2O, the products enter the IRMS. Three ions with m/z = 44 (12{sup left}C16{sup left}O{sub}2), 45 (13{sup left}C16{sup left}O{sub}2), 46 (12{sup left}C16{sup left}O18{sup left}O) are detected. The paper first introduces the origin of isotope difference among organic compounds. The instrumental principles and kinds of commercially available GC-IRMS are briefed thereafter. Based on the content of 5 review papers, the applications of GC-IRMS in food science, illicit drugs, environment science, and biodegradation fields are discussed.