Rapid Communications in Mass Spectrometry p. 343 - 350 (2019)
Update date:2022-08-29
Topics:
Greule, Markus
Keppler, Frank
Moossen, Heiko
Geilmann, Heike
Brand, Willi A.
Rationale: Stable hydrogen and carbon isotope ratios of methoxy groups (OCH3) of plant organic matter have many potential applications in biogeochemical, atmospheric and food research. So far, most of the analyses of plant methoxy groups by isotope ratio mass spectrometry have employed liquid iodomethane (CH3I) as the reference material to normalise stable isotope measurements of these moieties to isotope–δ scales. However, comparisons of measurements of stable hydrogen and carbon isotopes of plant methoxy groups are still hindered by the lack of suitable reference materials. Methods: We have investigated two methyl sulfate salts (HUBG1 and HUBG2), which exclusively contain carbon and hydrogen from one methoxy group, for their suitability as methoxy reference materials. Firstly, the stable hydrogen and carbon isotope values of the bulk compounds were calibrated against international reference substances by high-temperature conversion- and elemental analyser isotope ratio mass spectrometry (HTC- and EA-IRMS). In a second step these values were compared with values obtained by measurements using gas chromatography/isotope ratio mass spectrometry (GC/IRMS) where prior to analysis the methoxy groups were converted into gaseous iodomethane. Results: The 2H- and 13C isotopic abundances of HUBG1 measured by HTC- and EA-IRMS and expressed as δ-values on the usual international scales are ?144.5 ± 1.2 mUr (n = 30) and ?50.31 ± 0.16 mUr (n = 14), respectively. For HUBG2 we obtained ?102.0 ± 1.3 mUr (n = 32) and +1.60 ± 0.12 mUr (n = 16). Furthermore, the values obtained by GC/IRMS were in good agreement with the HTC- and EA-IRMS values. Conclusions: We suggest that both methyl sulfates are suitable reference materials for normalisation of isotope measurements of carbon of plant methoxy groups to isotope–δ scales and for inter-laboratory calibration. For stable hydrogen isotope measurements, we suggest that in addition to HUBG1 and HUBG2 additional reference materials are required to cover the full range of plant methoxy groups reported so far.
View MoreContact:+86-577-65618087-605
Address:Room 402, Unit 4 Xinhu Bldg. Waitan Ruian City, Zhejiang China.
Zhenjiang Haitong Chemical Industry Co., Ltd.
Contact:+86 (511) 8448-0369
Address:Baoyan Town, Dantu District, Zhenjiang City, Jiangsu, China
Changde Yungang Biotechnology Co., Ltd
website:http://www.cdyg.com
Contact:+86-736-7391178
Address:Qiaonan Industrial Park, Changde City, Hunan Province
Changzhou Baolong Chemical Industrial Co.,Ltd
website:http://www.czbaolong.com
Contact:0519-85720726 0519-85720721 13951213302
Address:No.1,Weihua Road,Xinbei District,Changzhou City,Jiangsu Province
Suzhou CarbonWell Pharma-Tech Co., Ltd
Contact:Tel: + 86 (0)512-8898-1216; + 86-18606258602
Address:2358 Changan Road, Wujiang Scientific Innovation Park, Wujiang, Jiangsu Province, P. R. China 215200
Doi:10.1002/cctc.201402561
(2015)Doi:10.1002/zaac.200700061
(2007)Doi:10.1139/V10-130
(2010)Doi:10.1016/S0040-4020(97)10205-8
(1998)Doi:10.1016/S0022-328X(02)01397-9
(2002)Doi:10.1016/j.tetlet.2007.08.039
(2007)