• Title/Summary/Keyword: GC-C/IRMS

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Validation and Applications of Gas Chromatography-Combustion/isotope Ratio Mass Spectrometric Method to Control Misuse of Androgens in Human

  • Lee, Kang-Mi;Kim, Ho-Jun;Jeong, Eun-Sook;Yoo, Hye-Hyun;Kwon, Oh-Seung;Jin, Chang-Bae;Kim, Dong-Hyun;Lee, Jae-Ick
    • Mass Spectrometry Letters
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    • v.2 no.2
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    • pp.33-36
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    • 2011
  • The misuse of anabolic androgenic steroids is of particular concern in sports and society. Thus, it is of great importance to discriminate endogenous steroids such as testosterone or testosterone prohormones from their chemically identical synthetic copies. In this study, gas chromatography-combustion/isotope ratio mass spectrometric (GC-C/IRMS) method has been developed and validated for discriminating the origin of anabolic androgenic steroids. The method involves the solid-phase extraction, enzymatic hydrolysis with ${\beta}$-glucuronidase, HPLC-fractionation for the cleanup and analysis by GC-C/IRMS. The difference(${\Delta}^{13}C$) of urinary ${\delta}^{13}C$ values between synthetic analogues and endogenous reference compounds (ERC) by GC-C/IRMS was used to elucidate the origin of steroids, and intra- and inter-day precision, specificity and isotope fractionation were evaluated. The present GC-C/IRMS method combined with HPLC cleanup was accurate and reproducible enough to be successfully applied to the test of urine sample from suspected anabolic steroid abusers.

CARBON ISOTOPE ANALYSES OF INDIVIDUAL HYDROCARBON MOLECULES IN BITUMINOUS COAL, OIL SHALE, AND MURCHISON METEORITE

  • Kim, Kyoung-Sook;Yang, Jong-Mann
    • Journal of Astronomy and Space Sciences
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    • v.15 no.1
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    • pp.163-174
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    • 1998
  • To study the origin of organic matter in meteorite, terrestrial rocks which contain or-ganic compounds similar to the ones found in carbonaceous chondrites are studied and compared with Muchison meteorite. Hydrocarbon molecules were extracted by benzene and methanol from bituminous coal and oil shale and the extracts were partitioned into aliphatic, aromatic, and polar fractions by silica gel column chromatography. Carbon isotopic ratios in each fractions were analysed by GC-C-IRMS. Molec-ular compound identifications were carried by GC-MS Engine. Bituminous coal and oil shale show the organic compound composition similar to that of meteorite. Oil shale has a wide range of ${\delta}^{13}C,-20.1%_0~-54.4%_0$ compared to bituminous coal, $-25.2%_0~34.3%_0$. Delta values of several molecular compounds in two terrestrial samples are different. They show several distinct distributions in isotopic ratios compared to those of meteorite; Murchison meteorite has a range of ${\delta}^13C\;from\;-13%_0\;to\;+30%_0$. These results provide interpretation for the source and the formation condition of each rock, in particular alteration and migration processes of organic matter. Especially, they show an important clue whether some hydrocarbon molecules observed in meteorite are indigenous or not.

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