Use of isotope ratio mass spectrometry to differentiate between endogenous steroids and synthetic homologues in cattle: A review

2013 ◽  
Vol 772 ◽  
pp. 1-15 ◽  
Author(s):  
Geert Janssens ◽  
Dirk Courtheyn ◽  
Sven Mangelinckx ◽  
Stéphanie Prévost ◽  
Emmanuelle Bichon ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
Isotope Ratio Mass Spectrometry ◽  
Endogenous Steroids

scholarly journals Measurement of δ18O and δ2H of water and ethanol in wine by Off-Axis Integrated Cavity Output Spectroscopy and Isotope Ratio Mass Spectrometry

2021 ◽  
Author(s):  
Xing Wang ◽  
Henk G. Jansen ◽  
Haico Duin ◽  
Harro A. J. Meijer
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
Isotope Analysis ◽  
Isotope Ratio Mass Spectrometry ◽  
Growth Conditions ◽  
The Other ◽  
H Nmr ◽  
Cavity Output ◽  
Pre Treatment ◽  
Output Laser

AbstractThere are two officially approved methods for stable isotope analysis for wine authentication. One describes δ18O measurements of the wine water using Isotope Ratio Mass Spectrometry (IRMS), and the other one uses Deuterium-Nuclear Magnetic Resonance (2H-NMR) to measure the deuterium of the wine ethanol. Recently, off-axis integrated cavity output (laser) spectroscopy (OA-ICOS) has become an easier alternative to quantify wine water isotopes, thanks to the spectral contaminant identifier (SCI). We utilized an OA-ICOS analyser with SCI to measure the δ18O and δ2H of water in 27 wine samples without any pre-treatment. The OA-ICOS results reveal a wealth of information about the growth conditions of the wines, which shows the advantages to extend the official δ18O wine water method by δ2H that is obtained easily from OA-ICOS. We also performed high-temperature pyrolysis and chromium reduction combined with IRMS measurements to illustrate the “whole wine” isotope ratios. The δ18O results of OA-ICOS and IRMS show non-significant differences, but the δ2H results of both methods differ much more. As the δ2H difference between these two methods is mainly caused by ethanol, we investigated the possibility to deduce deuterium of wine ethanol from this difference. The results present large uncertainties and deviate from the obtained 2H-NMR results. The deviation is caused by the other constituents in the wine, and the uncertainty is due to the limited precision of the SCI-based correction, which need to improve to obtain the 2H values of ethanol as alternative for the 2H-NMR method.

Linearity tests for secondary electron multipliers used in isotope ratio mass spectrometry

2001 ◽  
Vol 206 (1-2) ◽  
pp. 105-127 ◽  
Author(s):  
S Richter ◽  
S.A Goldberg ◽  
P.B Mason ◽  
A.J Traina ◽  
J.B Schwieters
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
Secondary Electron ◽  
Isotope Ratio Mass Spectrometry

scholarly journals Validation of the doubly labeled water method using off-axis integrated cavity output spectroscopy and isotope ratio mass spectrometry

2018 ◽  
Vol 314 (2) ◽  
pp. E124-E130 ◽  
Author(s):  
Edward L. Melanson ◽  
Tracy Swibas ◽  
Wendy M. Kohrt ◽  
Vicki A. Catenacci ◽  
Seth A. Creasy ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
New Technologies ◽  
Mean Squared Error ◽  
Intraclass Correlation ◽  
Isotope Ratio Mass Spectrometry ◽  
Carbon Dioxide Production ◽  
Urine Samples ◽  
Doubly Labeled Water ◽  
Cavity Output

When the doubly labeled water (DLW) method is used to measure total daily energy expenditure (TDEE), isotope measurements are typically performed using isotope ratio mass spectrometry (IRMS). New technologies, such as off-axis integrated cavity output spectroscopy (OA-ICOS) provide comparable isotopic measurements of standard waters and human urine samples, but the accuracy of carbon dioxide production (V̇co2) determined with OA-ICOS has not been demonstrated. We compared simultaneous measurement V̇co2 obtained using whole-room indirect calorimetry (IC) with DLW-based measurements from IRMS and OA-ICOS. Seventeen subjects (10 female; 22 to 63 yr) were studied for 7 consecutive days in the IC. Subjects consumed a dose of 0.25 g H218O (98% APE) and 0.14 g 2H2O (99.8% APE) per kilogram of total body water, and urine samples were obtained on days 1 and 8 to measure average daily V̇co2 using OA-ICOS and IRMS. V̇co2 was calculated using both the plateau and intercept methods. There were no differences in V̇co2 measured by OA-ICOS or IRMS compared with IC when the plateau method was used. When the intercept method was used, V̇co2 using OA-ICOS did not differ from IC, but V̇co2 measured using IRMS was significantly lower than IC. Accuracy (~1–5%), precision (~8%), intraclass correlation coefficients ( R = 0.87–90), and root mean squared error (30–40 liters/day) of V̇co2 measured by OA-ICOS and IRMS were similar. Both OA-ICOS and IRMS produced measurements of V̇co2 with comparable accuracy and precision compared with IC.

Preliminary study to characterize plastic polymers using elemental analyser/isotope ratio mass spectrometry (EA/IRMS)

Chemosphere ◽  
2017 ◽  
Vol 176 ◽  
pp. 47-56 ◽  
Author(s):  
Daniela Berto ◽  
Federico Rampazzo ◽  
Claudia Gion ◽  
Seta Noventa ◽  
Francesca Ronchi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
Isotope Ratio Mass Spectrometry ◽  
Preliminary Study
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