Inter-laboratory comparison of elemental analysis and gas chromatography/combustion/isotope ratio mass spectrometry. II. δ 15 N measurements of selected compounds for the development of an isotopic Grob test (original) (raw)
Related papers
Rapid Communications in Mass Spectrometry, 2009
This study was directed towards investigating suitable compounds to be used as stable isotope reference materials for gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) calibration. Several compounds were selected from those used in the 'Grob-test' mixture. Oxygen-and nitrogencontaining substances were added to these compounds to allow the mixture to be used as a possible multi-isotopic calibration tool for 2 H/ 1 H, 13 C/ 12 C, 15 N/ 14 N and 18 O/ 16 O ratio determinations. In this paper we present the results of d 13 C measurements performed by the consortium of the five laboratories taking part in this inter-calibration exercise. All the compounds were individually assessed for homogeneity, short-term stability and long-term stability by means of EA-IRMS, as required by the bureau communitaire de reference (BCR) Guide for Production of Certified Reference Materials. The results were compared then with the GC-C-IRMS measurements using both polar and non-polar columns, and the final mixture of selected compounds underwent a further certification exercise assessing limits of accuracy and reproducibility under specified GC-C-IRMS conditions.
Applied gas chromatography coupled to isotope ratio mass spectrometry
Compound-specific isotope analysis (CSIA) by isotope ratio mass spectrometry (IRMS) following on-line combustion (C) of compounds separated by gas chromatography (GC) is a relatively young analytical method. Due to its ability to measure isotope distribution at natural abundance level with great accuracy and high precision, GC/C–IRMS has increasingly become the method of choice in authenticity control of foodstuffs and determination of origin in archaeology, geochemistry, and environmental chemistry. In combination with stable isotope labelled compounds, GC/C–IRMS is also used more and more in biochemical and biomedical application as it offers a reliable and risk-free alternative to the use of radioactive tracers. The literature on these topics is reviewed from the advent of commercial GC/C–IRMS systems in 1990 up to the beginning of 1998. Demands on sample preparation and quality of GC separation for GC/C–IRMS are discussed also.
Earth Sciences, 2012
This paper reviews the experimental procedures of the Gas Chromatography-Mass Spectrometry (GC-MS) technique. The objectives of this study are to present a step-by-step procedure involved in the GC-MS analysis and interpretations of the resulting data both qualitatively and quantitatively, and to identify the possible sources of analytical errors that may be encountered by young inexperienced organic geochemists. The overall process encompasses ultrasonic solvent extraction, fractionation and GC-MS analysis itself. The qualitative and quantitative information obtained from the GC-MS interpretations when integrated together is capable of giving us an insight into the source or origin, depositional environment and level thermal maturity of the analysed sample. The possible sources of analytical errors may include contamination, measurement errors, mechanical/instrumental errors, fractionation errors, and loading errors on the GC. Analytical geochemists must therefore be aware of these errors among others in order to minimise them to the reasonable level. It is recommended that, if weak signals result from the GC-MS analysis of a fraction, such a fraction should be prepared in higher concentration and re-run using selected ion monitoring (SIM) mode so as to enhance signal to noise ratio, and that the GC-MS data should always be interpreted with GC-MS softwares with biomarkers definitions in order to obtain more reliable and robust interpretations.
E5 - Gas Chromatography (GC) for Qualitative and Quantitative Analysis
A0155410U Aims: 1. Determine Height Equivalent to a Theoretical Plate (HETP) and use it to obtain constants of the van Deemter's equation. 2. Analyse sample A, B, C and unknown sample, D, qualitatively and quantitatively. 3. Determine and compare experimental and theoretical effective carbon number (ECN) of the compounds in sample A, B and C. Results and Discussion: Determination of HETP and constants of van Deemter's equation Shimadzu GC-2014 is used in this experiment, with a Flame Ionisation Detector (FID) and
Analytical and Bioanalytical Chemistry, 2006
For the past 25 years the National Institute of Standards and Technology (NIST) has developed certified reference materials (CRMs), known as standard reference materials (SRMs), for determination of organic contaminants in environmental matrices. Assignment of certified concentrations has usually been based on combining results from two or more independent analytical methods. The first-generation environmental-matrix SRMs were issued with certified concentrations for a limited number (5 to 10) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Improvements in the analytical certification approach significantly expanded the number and classes of contaminants determined. Environmental-matrix SRMs currently available include air and diesel particulate matter, coal tar, marine and river sediment, mussel tissue, fish oil and tissue, and human serum, with concentrations typically assigned for 50 to 90 organic contaminants, for example PAHs, nitro-substituted PAHs, PCBs, chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs).
Gas chromatography-Mass spectrometry
Capítol del llibre: …, 2012
This article briefly describes the possible configurations of the gas chromatography-mass spectrometry (GC/MS) technology available at the CCiTUB. Some developed examples of different applications are shown.
Mixture analysis by gas chromatography/Fourier transform infrared spectrometry/mass spectrometry
Analytical Chemistry, 1982
Carbon Black. Table IV reports the analysis of the toluene total extract of a carbon black similar to that recently described by Rosenkranz et al. as Carbon black B (20). In addition to the reported nitropyrenes, several other nitroarenes were determined. In this sample the level of nitro compounds was relatively high. The ECNICI technique proves to be a very rapid and sensitive screening method for such samples, as no workup of the total extract is needed. Urban Air Particulate Matter. The present method has also been applied to determine nitro-PAH in extracts of urban air particulate matter. After fractionation of the extract by normal phase silica high-performance liquid chromatography, the occurrence of 1-and 2-nitronaphthalene, two isomers of nitroanthracene, methylnitroanthracene, 3-nitrofluoranthene, and l-nitropyrene was demonstrated in the moderately polar fraction by the ECNICI technique. A detailed discussion of this application is given elsewhere (21).