Knowledge Base

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  • IRMS
  • Delta V Advantage
  • Flash 1112 HT
  • GC
  • 15N
  • Taurine

Determination of the natural abundance d15N of taurine by gas chromatography–isotope ratio measurement mass spectrometry

Illa Tea*, Ingrid Antheaume, Jorick Besnard and Richard J. Robins

Elucidation of Biosynthesis by Isotopic Spectrometry Group, Unit for Interdisciplinary Chemistry: Synthesis-Analysis-Modelling University of Nantes–CNRS UMR6230, 2 rue de la Houssinie`re, BP 92208, F-44322 Nantes, France

Rapid Communications in Mass Spectrometry (2010), V24, pp3380–3386, doi: 10.1002/rcm.4784

Goal: The measurement of the nitrogen isotope ratio of taurine (2-aminoethanesulphonic acid) in biological samples has a large number of potential applications. Taurine is a small water-soluble molecule which is notoriously difficult to analyze due to its polarity and functionality. A method is described which allows the determination of the natural abundance d15N values of taurine and structural analogues, such as 3-amino-1-propanesulphonic acid (APSA), by isotope ratio mass spectrometry interfaced to gas chromatography (GC-irm-MS).

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Thermo Scientific LC IsoLink™

Thermo Fisher Scientific, Bremen, Germany

BR30039

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  • IRMS
  • Gas Bench
  • Nitrogen Isotopes
  • Nitrification

Characteristics of the delta 15N (NO3-) distribution and its drivers in the Changjiang River estuary and adjacent waters

Wentao Wang (1,2,3), Zhiming Yu (1,2), Xiuxian Song (1,2), Zaixing Wu (1,2), Yongquan Yuan (1,2), Peng Zhou (1,2,3) and Xihua Cao (1,2)

1) Key Laboratory of Marine Ecology and Environmental Science, Institute of Oceanology, Chinese Academy of Sciences, 2) Laboratory of Marine Ecology and Environmental Science, Qingdao National laboratory for Marine Science and Technology, 3) University of Chinese Academy of Sciences, 4

Chinese Journal of Oceanology and Limnology (2016), pp1-16

Goal: In this study, we conducted investigations in the Changjiang (Yangtze) River estuary and adjacent waters (CREAW) in June and November of 2014. We collected water samples from different depths to analyze the nitrogen isotopic compositions of nitrate, nutrient concentrations (including inorganic N, P, and Si), and other physical and biological parameters, along with the vertical distribution and seasonal variations of these parameters. The compositions of nitrogen isotope in nitrate were measured with the denitrifier method.

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  • European regulation
  • 18O
  • wine

Chapter 43: DETERMINATION OF THE ISOTOPIC RATIO 18O/16O OF THE WATER CONTENT IN WINES

European Commission

EU Brussels, Belgium

COMMISSION REGULATION (EC) No 822/97 of 6 May 1997; Official Journal of the European Communities

Goal: The isotopic ratio 18O/16O is determined by mass spectrometry of isotopic ratios (MSIR) from ionic currents m/z 46 (12C16O18O) and m/z 44 (12C16O2) produced by carbon dioxide obtained after an exchange with the water in wine according to the reaction: C16O2 + H218O ↔ C16O18O + H216O.

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  • IRMS
  • HPLC
  • Carbon isotopes
  • Amino acids

A three-phase liquid chromatographic method for d13C analysis of amino acids from biological protein hydrolysates using liquid chromatography–isotope ratio mass spectrometry

Colin I. Smith, Benjamin T. Fuller, Kyungcheol Choy, Michael P. Richards

Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig 04103, Germany

Analytical Biochemistry (2009), V390, pp165–172, doi: 10.1016/j.ab.2009.04.014

Goal: We report a three-phase chromatographic method for the separation and analysis of d13C values of underivatized amino acids from biological proteins (keratin, collagen, and casein) using liquid chromatography–

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  • GC-IRMS
  • Nitrogen isotopes
  • Zooplankton

Environmental perturbation effects on baseline d15N values and zooplankton trophic flexibility in the southern California Current Ecosystem

Moira Décima (1), Michael R. Landry (1) and Brian N. Popp (2)

1) Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California, 2) Department of Geology and Geophysics, University of Hawaii, Honolulu, Hawaii

Limnology and Oceanography (2013), V58(2), pp624–634 , doi: 10.4319/lo.2013.58.2.0624

Goal: Nitrogen isotopic compositions of zooplankton in the California Current Ecosystem (CCE) are known to vary over inter-annual scales of climate variability, but the extent to which those changes are driven by variations in baseline phytoplankton d15N values vs. zooplankton trophic position (TP) is poorly resolved. We use field samples collected during a large natural environmental perturbation, the 1998–1999 alternation between El Niño and La Niña states, to test the ability of large dominant CCE zooplankton Euphausia pacifica and Calanus pacificus to alter their TPs in response to environmental variability.

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  • LC IsoLink™
  • Compound Specific Isotope Analysis
  • Honey
  • HPLC
  • Isotope Ratio MS
  • Sugar

irm-LC/MS: δ^13C of Carbohydrates in Honey

Andreas W. Hilkert, Michael Krummen, Dieter Juchelka

Thermo Fisher Scientific, Bremen, Germany

AN30024

Goal: Sugars are one of the biggest and most common families of molecules in life. They serve as energy resources, the backbone of DNA and RNA, the carrier of biologically active compounds and as structure building material of plants. Sugars can carry information of their origin and processing.

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  • HR-ICPMS
  • Element 2 XR
  • Neptune Plus
  • B isotopes
  • Foraminifera

Determination of δ 11B by HR-ICP-MS from Mass Limited Samples: Application to Natural Carbonates and Water Samples

Sambuddha Misra (1), Robert Owen (1,2), Joanna Kerr (1), Mervyn Greaves (1) and Henry Elderfield (1)

1) University of Cambridge, Department of Earth Sciences, Godwin Laboratory for Paleoclimate Research, Downing Street, Cambridge CB2 3EQ, United Kingdom, 2) University of Oxford, Department of Earth Sciences, Oxford OX1 3PR, United Kingdom

Geochimica et Cosmochimica Acta (2014), V140, pp531-552, doi: 10.1016/j.gca.2014.05.047

Goal: We present an improved method for accurate and precise determination of the boron isotopic composition (11B/10B) of carbonate and water samples using a mineral acid matrix and HR-ICP-MS. Our method for δ11B determination utilizes a micro-distillation based boron purification technique for both carbonate and seawater matrices.

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  • MC-ICPMS
  • Neptune
  • Li Isotopes
  • Rock Standards

Lithium Isotope Measurements Using Thermo Scientific NEPTUNE Multicollector ICP-MS

Claudia Bouman and Johannes B. Schwieters

Thermo Fisher Scientific, Bremen, Germany

AN30014

Goal: Here, we report on the short-term reproducibility of Li isotope analyses of NIST L-SVEC lithium carbonate standard and two international rock standards, BHVO-1 (USGS) and JG-2 (GSJ) with the Thermo Scientific NEPTUNE MC-ICP-MS.

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  • MC-ICPMS
  • Neptune
  • Sr
  • Nd

Nd and Hf Isotope Measurements Using a Double Focusing Multicollector ICP-MS

Stefan Weyer (1) and Johannes B. Schwieters (2)

1) Goethe-Universität, Frankfurt, Germany, 2) Thermo Fisher Scientific, Bremen, Germany

AN30013

Goal: This report describes the short- and long-term performance of the NEPTUNE. The short-term reproducibility is demonstrated by the measurement of an Nd standard solution over 3.5 hrs. The long-term reproducibility of Hf isotope composition measurements is measured over a 9 month period.

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  • IRMS
  • EA/GC/LC IsoLink
  • Official Methods
  • Isotope Fingerprints
  • Food Authenticity
  • Adulteration
  • Fraud

Are there official methods for food and beverage product origin, authenticity and label claims?

Thermo Fisher Scientific, Bremen, Germany

SN30414

Goal: This smart note shows official methods for isotope analysis using isotope ratio mass spectrometry.

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  • IRMS
  • EA/GC/LC IsoLink
  • Isotope Fingerprints
  • Food Authenticity
  • Adulteration
  • Fraud

How can stable isotopes be used to determine origin and authenticity of food and beverage products?

Thermo Fisher Scientific, Bremen, Germany

SN30410

Goal: This smart note answers the question how isotopes can be used to determine origin and authenticity of food and beverage products.

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  • IRMS
  • EA/GC/LC IsoLink
  • Isotope Fingerprints
  • Food Authenticity
  • Adulteration
  • Fraud

Food and beverage fraud prevention using stable isotope fingerprints

Christopher Brodie, Oliver Kracht, Dieter Juchelka, Jens Radke and Andreas Hilkert

Thermo Fisher Scientific, Bremen, Germany

PN30397

Goal: This note demonstrates how stable isotope fingerprints offer conclusive answers on questions associated with origin, adulteration and correct labeling of food and beverage products.

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  • IRMS
  • EA IsoLink
  • Isotope Fingerprints
  • Food Fraud
  • Coffee
  • Geographical Origin

EA-IRMS: Tracing the geographical origin of coffee using isotope fingerprints

Maryam Weigt, Christopher Brodie and Oliver Kracht

Thermo Fisher Scientific, Bremen, Germany

AN30418

Goal: In this application note we show hydrogen and oxygen stable isotope measurements on roasted coffee samples measured with the Thermo Scientific™ EA IsoLink™ IRMS System. We were able to trace the origin of coffee beans based on unique trends observed from their isotopic fingerprints.

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  • IRMS
  • EA IsoLink
  • Isotope Fingerprints
  • Food Fraud
  • Sugar

EA-IRMS: Testing sugar package label claims using carbon isotope fingerprints

Maryam Weigt, Christopher Brodie and Oliver Kracht

Thermo Fisher Scientific, Bremen, Germany

AB30424

Goal: In this application brief we show carbon isotope measurements on sugar and distinguish between cane and beet sugars and verify package label claims