scholarly journals Automatic AMS Sample Combustion and CO2 Collection

Radiocarbon ◽  
2001 ◽  
Vol 43 (2A) ◽  
pp. 293-298 ◽  
Author(s):  
A T Aerts-Bijma ◽  
J van der Plicht ◽  
H A J Meijer
Keyword(s):  
Mass Spectrometry ◽  
Memory Effect ◽  
Mass Spectrometer ◽  
Accelerator Mass Spectrometry ◽  
Isotope Ratio ◽  
Memory Effects ◽  
Isotope Ratio Mass Spectrometer ◽  
Cryogenic Trapping ◽  
Co2 Collection

In Groningen, all organic samples for accelerator mass spectrometry (AMS) are combusted in an automatic Elemental Analyzer, coupled to an Isotope Ratio Mass Spectrometer and Cryogenic Trapping System. The Gas Chromatographic (GC) column, part of the Elemental Analyzer system, appeared to be the main cause for memory effects. Therefore we modified the Elemental Analyzer, such that the trapped CO2 no longer passed the GC column. Our system modification reduced the memory effect significantly, as shown by lower radiocarbon concentration values for anthracite backgrounds, and a much smaller spread in these values. Our modified system can perform up to 40 combustions unattended in about 6 hr.

scholarly journals Isotope-Ratio and Background Corrections for Accelerator Mass Spectrometry Radiocarbon Measurements

Radiocarbon ◽  
1990 ◽  
Vol 32 (2) ◽  
pp. 135-142 ◽  
Author(s):  
D J Donahue ◽  
T W Linick ◽  
A J T Jull
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrometer ◽  
Accelerator Mass Spectrometry ◽  
Isotope Ratio ◽  
Isotope Ratios ◽  
Sample Contamination ◽  
Accelerator Mass Spectrometer

We present here the method we use to convert to radiocarbon ages (14C/13C) ratios measured in the Arizona Accelerator Mass Spectrometer facility. We describe the procedures we use to convert sample and standard isotope ratios to values appropriate for calculation of radiocarbon ages. We also discuss, in some detail, corrections to account for sample contamination.

A liquid chromatography – mass spectrometry method to measure 13C-isotope enrichment for DNA stable-isotope probing

2012 ◽  
Vol 58 (3) ◽  
pp. 287-292 ◽  
Author(s):  
Julie Auclair ◽  
François Lépine ◽  
Richard Villemur
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Stable Isotope ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Bacterial Species ◽  
Isotope Ratio Mass Spectrometry ◽  
Stable Isotope Probing ◽  
Wide Range ◽  
Isotope Ratio Mass Spectrometer

DNA stable-isotope probing (DNA-SIP) is a cultivation-independent technique that makes it possible to associate metabolic function and taxonomic identity in a wide range of terrestrial and aquatic environments. In DNA-SIP, DNA is labeled via the assimilation of a labeled growth substrate that is subsequently used to identify microorganisms involved in assimilation of the substrate. However, the labeling time has to be sufficient to obtain labeled DNA but not so long such that cross-feeding of 13C-labeled metabolites from the primary consumers to nontarget species can occur. Confirmation that the DNA is isotopically labeled in DNA-SIP assays can be achieved using an isotope ratio mass spectrometer. In this study, we describe the development of a method using liquid chromatography (HPLC) coupled to a quadrupole mass spectrometer (QMS) to measure the 13C enrichment of thymine incorporated into DNA in Escherichia coli cultures fed with [13C]acetate. The method involved the hydrolysis of DNA extracted from the cultures that released the nucleotides, followed by the separation of the thymine by HPLC on a reverse-phase C8 column in isocratic elution mode and the detection and quantification of 13C-labeled thymine by QMS. To mimic a DNA-SIP assay, a DNA mixture was made using 13C-labeled E. coli DNA with DNA extracted from five bacterial species. The HPLC–MS method was able to measure the correct proportion of 13C-DNA in the mix. This method can then be used as an alternative to the use of isotope ratio mass spectrometry in DNA-SIP assays.

scholarly journals Quantitative analysis and detection of chaptalization and watering down of wine using isotope ratio mass spectrometry

2019 ◽  
Vol 15 ◽  
pp. 02007
Author(s):  
I. Smajlovic ◽  
D. Wang ◽  
M. Túri ◽  
Z. Qiding ◽  
I. Futó ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Stable Isotope ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Alcoholic Fermentation ◽  
Isotope Ratio Mass Spectrometry ◽  
Wine Production ◽  
New Approach ◽  
Isotope Ratio Mass Spectrometer ◽  
Production Practices

In early 1990's European Union has established new isotopic approach for detection of wine authenticity. In this article we setup the possibility of using new approach using new EIM – Module – IRMS (Ethanol Isotope Measurement – Module – Isotope Ratio Mass Spectrometry) instrumental technique and new analytical parameter δDn(δ2Hn) wine ethanol value, which represents δ2H value of non-exchangeable hydrogen stable isotope ratio in ethanol, with other isotopic species (δ18O values in wine water) to improve detection of illegal wine production practices such as addition of sugar and/or dilution with water. Total of 42 wine samples were analyzed. 10 wine samples (out of 42) were prepared from grapes by alcoholic fermentation and analyzed for δDn values of ethanol. 19 wine samples (out of 42) were collected from wine producers in Serbia plus 1 wine samples designated from United States was taken from Serbian market and analyzed for δDn values of ethanol, δ18O values in wine water and also δ13C values in wine ethanol. Furthermore 9 wine samples (out of 42) were taken from Hungarian market and analyzed for δDn values of ethanol, and also 3 wine samples (out of 42) were taken from Austrian market and analyzed for δDn values of ethanol. All experiments were done in 4 isotope laboratories located in US, Austria, Hungary and People's Republic of China. δDn values of ethanol were measured by using EIM Module connected to FlashHT 2000 pyrolizer (one laboratory – Imprint Analytics GmbH, Austria), while in other 3 laboratories (US – COIL – Cornell University, Stable Isotope Laboratory, Hungary – Isotoptech Ltd, Debrecen, Hungary and China – C.N.R.I.F.F.I. – China National Institute of Food and Fermentation Industries Limited) EIM Module was connected to TC/EA (High Temperature Conversion Elemental Analyzer). Peripherals in all laboratories were further interfaced with isotope ratio mass spectrometer. Furthermore δ18O values in wine water were measured by using Gas Bench II interfaced also with isotope ratio mass spectrometer (one laboratory – US). Obtained results from all 4 laboratories have shown that this new approach which uses δDn in wine ethanol is more effective in improving detection of illegal wine production practices (sugar enrichment and water dilution) and origin of ethanol, and also detecting the addition of corn or beet sugar, sugar syrup to wine, or dilution of grape must with water prior to alcoholic fermentation. Keywords: Wine authenticity; EIM – Module – IRMS; Stable Isotope; Isotope Ratio Mass Spectrometry; Wine; Watering; Chaptalization.

scholarly journals Status report of the Trondheim Radiocarbon Laboratory

Radiocarbon ◽  
2019 ◽  
Vol 61 (6) ◽  
pp. 1963-1972 ◽  
Author(s):  
Martin Seiler ◽  
Pieter M Grootes ◽  
John Haarsaker ◽  
Sylvie Lélu ◽  
Izabela Rzadeczka-Juga ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Sample Preparation ◽  
Accelerator Mass Spectrometry ◽  
Isotope Ratio ◽  
National Laboratory ◽  
Age Determination ◽  
Status Report ◽  
Data Handling ◽  
Isotope Ratio Mass Spectrometer ◽  
Cleaning Procedures

ABSTRACTThe Trondheim radiocarbon (14C) laboratory has evolved from a traditional radiocarbon decay counting laboratory to an accelerator mass spectrometry (AMS) facility primarily measuring 14C. This evolution required adjustments in sample preparation and data handling to match the capacity of the AMS system and reduction in sample sizes to about 1 mgC. We summarize here the steps involved in dating a sample at the National Laboratory for Age Determination in Trondheim, Norway. These include the structure of our sample database for information handling, sample cleaning procedures for different sample types, our reduction systems, both an automated EA-based system for regular use and a manual system for more challenging samples, and data evaluation. We will also briefly summarize the capabilities of our isotope-ratio mass spectrometer.

scholarly journals A STUDY ON CARBON ISOTOPE OF CO2 AND CH4 IN WESTERN DIENG PLATEU BY GAS CHROMATOGRAPHY- ISOTOPE RATIO MASS SPECTROMETER (GC-IRMS)

2010 ◽  
Vol 5 (1) ◽  
pp. 11-14
Author(s):  
Hanik Humaida
Keyword(s):  
Gas Chromatography ◽  
Carbon Isotope ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Isotope Analysis ◽  
Ionization Detector ◽  
Volcanic Gas ◽  
Porapak Q ◽  
Flame Ionization ◽  
Isotope Ratio Mass Spectrometer

The carbon isotope can be used to evaluate volcanism phenomenon of volcano. The study of carbon isotope of CO2 and CH4 was carried out in western Dieng Plateau by mass-spectrometer. Before analysis, sampel was separated by gas chromatography using a Porapak-Q column and a FID (Flame Ionization Detector) detector. The gas was oxidized by copper oxide at 850oC before being ionized in mass-spectrometer for isotope analysis. The CO2 content in Candradimuka crater (-4.10 O/OO), indicated that the gas may be as volcanic gas. The other CO2 from Sumber and western Gua Jimat, had isotope value  of -10.05 and -12.07 O/OO, respectively, indicating contamination from crustal and subduction material. The carbon isotope of CH4 gas from Pancasan village was -63.42 O/OO, that may be categorized as biogenic gas.   Keywords: isotope, CO2, CH4, Dieng.

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