TY - JOUR
T1 - Organic Reference Materials for Hydrogen, Carbon, and Nitrogen Stable Isotope-Ratio Measurements
T2 - Caffeines, n-Alkanes, Fatty Acid Methyl Esters, Glycines, L-Valines, Polyethylenes, and Oils
AU - Schimmelmann, Arndt
AU - Qi, Haiping
AU - Coplen, Tyler B.
AU - Brand, Willi A.
AU - Fong, Jon
AU - Meier-Augenstein, Wolfram
AU - Kemp, Helen F.
AU - Toman, Blaza
AU - Ackermann, Annika
AU - Assonov, Sergey
AU - Aerts-Bijma, Anita T.
AU - Brejcha, Ramona
AU - Chikaraishi, Yoshito
AU - Darwish, Tamim
AU - Elsner, Martin
AU - Gehre, Matthias
AU - Geilmann, Heike
AU - Groeing, Manfred
AU - Helie, Jean-Francois
AU - Herrero-Martin, Sara
AU - Meijer, Harro A. J.
AU - Sauer, Peter E.
AU - Sessions, Alex L.
AU - Werner, Roland A.
PY - 2016/4/19
Y1 - 2016/4/19
N2 - An international project developed, quality-tested, and determined isotope-delta values of 19 new organic reference materials (RMs) for hydrogen, carbon, and nitrogen stable isotope-ratio measurements, in addition to analyzing pre-existing RMs NBS 22 (oil), IAEA-CH-7 (polyethylene foil), and IAEA-600 (caffeine). These new RMs enable users to normalize measurements of samples to isotope-delta scales. The RMs span a range of delta H-2(VSMOW-SLAP) values from -210.8 to +397.0 mUr or parts per thousand, for delta C-13(VPDB-LSVEC) from -40.81 to +0.49 mUr and for delta N-15(Air) from -5.21 to +61.53 mUr. Many of the new RMs are amenable to gas and liquid chromatography. The RMs include triads of isotopically contrasting caffeines, C-16 n-alkanes, n-C-20-fatty acid methyl esters (FAMEs), glycines, and L-valines, together with polyethylene powder and string, one n-C-17-FAME, a vacuum oil (NBS 22a) to replace NBS 22 oil, and a H-2-enriched vacuum oil. A total of 11 laboratories from 7 countries used multiple analytical approaches and instrumentation for 2-point isotopic normalization against international primary measurement standards. The use of reference waters in silver tubes allowed direct normalization of delta H-2 values of organic materials against isotopic reference waters following the principle of identical treatment. Bayesian statistical analysis yielded the mean values reported here. New RMs are numbered from USGS61 through USGS78, in addition to NBS 22a. Because of exchangeable hydrogen, amino acid RMs currently are recommended only for carbon- and nitrogen-isotope measurements. Some amino acids contain C-13 and carbon-bound organic H-2-enrichments at different molecular sites to provide RMs for potential site-specific isotopic analysis in future studies.
AB - An international project developed, quality-tested, and determined isotope-delta values of 19 new organic reference materials (RMs) for hydrogen, carbon, and nitrogen stable isotope-ratio measurements, in addition to analyzing pre-existing RMs NBS 22 (oil), IAEA-CH-7 (polyethylene foil), and IAEA-600 (caffeine). These new RMs enable users to normalize measurements of samples to isotope-delta scales. The RMs span a range of delta H-2(VSMOW-SLAP) values from -210.8 to +397.0 mUr or parts per thousand, for delta C-13(VPDB-LSVEC) from -40.81 to +0.49 mUr and for delta N-15(Air) from -5.21 to +61.53 mUr. Many of the new RMs are amenable to gas and liquid chromatography. The RMs include triads of isotopically contrasting caffeines, C-16 n-alkanes, n-C-20-fatty acid methyl esters (FAMEs), glycines, and L-valines, together with polyethylene powder and string, one n-C-17-FAME, a vacuum oil (NBS 22a) to replace NBS 22 oil, and a H-2-enriched vacuum oil. A total of 11 laboratories from 7 countries used multiple analytical approaches and instrumentation for 2-point isotopic normalization against international primary measurement standards. The use of reference waters in silver tubes allowed direct normalization of delta H-2 values of organic materials against isotopic reference waters following the principle of identical treatment. Bayesian statistical analysis yielded the mean values reported here. New RMs are numbered from USGS61 through USGS78, in addition to NBS 22a. Because of exchangeable hydrogen, amino acid RMs currently are recommended only for carbon- and nitrogen-isotope measurements. Some amino acids contain C-13 and carbon-bound organic H-2-enrichments at different molecular sites to provide RMs for potential site-specific isotopic analysis in future studies.
KW - MASS-SPECTROMETRY
KW - GAS-CHROMATOGRAPHY
KW - DELTA-C-13
KW - NORMALIZATION
KW - CALIBRATION
KW - GUIDELINES
KW - PRECISION
KW - ABUNDANCE
KW - CHROMIUM
KW - OXYGEN
U2 - 10.1021/acs.analchem.5b04392
DO - 10.1021/acs.analchem.5b04392
M3 - Article
C2 - 26974360
SN - 0003-2700
VL - 88
SP - 4294
EP - 4302
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 8
ER -