Results 241 to 250 of about 5,973,776 (275)

Profiling of urinary formestane and confirmation by isotope ratio mass spectrometry

Steroids, 2013
Formestane (F, androst-4-en-4-ol-3,17-dione) is an irreversible aromatase inhibitor with the ability to suppress the estrogen production from anabolic steroids. Consequently, F is mentioned on the World Anti-Doping Agency (WADA) prohibited list and because studies have shown that F is produced endogenously in small amounts, a threshold for urinary ...
Michael, Polet, Pieter, Van Renterghem, Wim, Van Gansbeke, Peter, Van Eenoo   +3 more
openaire   +2 more sources

Fast Gas Chromatography Combustion Isotope Ratio Mass Spectrometry

Analytical Chemistry, 2007
We report here the first coupling of fast GC to IRMS, in a system capable of 250 ms peak widths (fwhm) at 1 mL/min flow rates, one-fifth as narrow as any previously reported GCC-IRMS system. We developed an optimized postcolumn interface that results in minimal peak broadening, using a programmable temperature vaporization injector in place of a rotary
Gavin L, Sacks, Ying, Zhang, J Thomas, Brenna   +2 more
openaire   +2 more sources

Isotope Ratio Measurements with Elemental-Mode Electrospray Mass Spectrometry

Analytical Chemistry, 1996
The isotope ratio capabilities of an electrospray ionization source interfaced to a quadrupole mass spectrometer are described. With the instrument operated in the metal ion mode, isotope measurements of Ag, Tl, and Pb are conducted using elemental ions produced from 1 × 10(-)(4) M solutions of metal nitrates or acetates in methanol.
M E, Ketterer, J P, Guzowski
openaire   +2 more sources

Acquisition and processing of data for isotope-ratio-monitoring mass spectrometry

Organic Geochemistry, 1994
Methods are described for continuous monitoring of signals required for precise analyses of 13C, 18O, and 15N in gas streams containing varying quantities of CO2 and N2. The quantitative resolution (i.e. maximum performance in the absence of random errors) of these methods is adequate for determination of isotope ratios with an uncertainty of one part
M P, Ricci, D A, Merritt, K H, Freeman, J M, Hayes   +3 more
openaire   +2 more sources

Carbon Isotope Ratio Analysis of Steroids by High-Temperature Liquid Chromatography-Isotope Ratio Mass Spectrometry

Analytical Chemistry, 2014
Generally, compound-specific isotope analysis of steroids is carried out by gas chromatography combined with isotope ratio mass spectrometry. Thus, a derivatization of the steroids prior to the measurement is compulsory, and a correction of the isotopic data is often necessary.
Zhang, Lijun, Thevis, Mario, Piper, Thomas, Jochmann, Maik, Wolbert, Jens-Benjamin, Kujawinski, Dorothea M., Wiese, Steffen, Teutenberg, Thorsten, Schmidt, Torsten Claus   +8 more
openaire   +2 more sources

ForensicApplications of Isotope Ratio Mass Spectrometry

2003
Meier-Augenstein, Wolfram, Liu, R.H.
openaire   +2 more sources

Isotope Ratio Studies Using Mass Spectrometry

1999
Wieser, M., Brand, W.
openaire   +3 more sources

Isotopic and Elemental Analysis of Apple and Orange Juice by Isotope Ratio Mass Spectrometry (IRMS) and Inductively Coupled Plasma – Mass Spectrometry (ICP-MS)

Analytical Letters, 2021
Dana Alina Magdas, Gabriela Cristea, Ioana Feher   +2 more
exaly  

Mass spectrometry and natural variations of iron isotopes

Mass Spectrometry Reviews, 2006
Nicolas Dauphas, Olivier Rouxel
exaly  

Multi-isotope imaging mass spectrometry quantifies stem cell division and metabolism

Nature, 2012
Matthew L Steinhauser, Christelle Guillermier   +1 more
exaly