Recent trends and developments in pyrolysis-gas chromatography: review

Pyrolysis-gas chromatography (Py-GC) has become well established as a simple, quick and reliable analytical technique for a range of applications including the analysis of polymeric materials. Recent developments in Py-GC technology and instrumentation include laser pyrolysis and non-discriminating pyrolysis. Progress has also been made in the detection of low level polymer additives with the use of novel Py-GC devices. Furthermore, it has been predicted that future advances in separation technology such as the use of comprehensive two-dimensional gas chromatography will further enhance the analytical scope of Py-GC

Introductory Chapter: Gas Chromatography - The Most Versatile Analytical Technique

Gas chromatography (GC) is a type of chromatography. According to the International Union of Pure and Applied Chemistry (IUPAC) recommendation, gas chromatography is defined as a separation technique in which the mobile phase is a gas. Gas chromatography is always carried out in a column [1]. GC is a separation and detection method for sample mixtures, whose components can be volatilized without thermal decomposition

Influence of vineyard managements on aroma of Merlot wines.

The objective of this study is to evaluate the influence of vineyard managements on aroma of Campanha Gaúcha Merlot wines through quantitative descriptive analysis (QDA), gas chromatography ? olfactometry (GC - O) and comprehensive two - dimensional gas chromatography coupled to time-of -flight mass spectrometric detection (GC × GC/TOFMS)

GAS CHROMATOGRAPHY-MASS SPECTROSCOPY ANALYSIS OF PHYTOCHEMICAL CONSTITUENTS OF METHANOLIC EXTRACT OF NEEDLES OF PINUS WALLICHIANA

ABSTRACTObjective: To investigate the phytoconstituents of methanolic extracts of a conifer Pinus wallichiana using gas chromatography-mass spectroscopy(GC-MS), which is famous for its timber quality, resins and oils.Methods: The present investigation was carried out to determine the possible chemical constituents present in the methanolic extracts in the needlesof P. wallichiana.Results: The result of the GC-MS confirmed the presence of 38 compounds. Momeinositol (43.27%), 9, 12-octadecanoic acid, 2 (12.52%) pentadecanoicacid (4.12%) and dibutyl phthalate (3.34%) were the major compound found through the GC-MS analysis.Conclusion: The presence of various compounds in the methanolic extract of P. wallichiana confirms its relevance not only for pharmaceuticalpurpose but for various industrial purposes too.Keywords: Pinus wallichiana, Gas chromatography-mass spectroscopy (GC-MS), Gas chromatography-mass spectroscopy of plant extract, Gaschromatography-mass spectroscopy of conifer, Gas chromatography-mass spectroscopy profiling

Identifying metabolites by integrating metabolome databases with mass spectrometry cheminformatics.

Novel metabolites distinct from canonical pathways can be identified through the integration of three cheminformatics tools: BinVestigate, which queries the BinBase gas chromatography-mass spectrometry (GC-MS) metabolome database to match unknowns with biological metadata across over 110,000 samples; MS-DIAL 2.0, a software tool for chromatographic deconvolution of high-resolution GC-MS or liquid chromatography-mass spectrometry (LC-MS); and MS-FINDER 2.0, a structure-elucidation program that uses a combination of 14 metabolome databases in addition to an enzyme promiscuity library. We showcase our workflow by annotating N-methyl-uridine monophosphate (UMP), lysomonogalactosyl-monopalmitin, N-methylalanine, and two propofol derivatives

Characterization and Quantification of Isoprene-Derived Epoxydiols in Ambient Aerosol in the Southeastern United States

Isoprene-derived epoxydiols (IEPOX) are identified in ambient aerosol samples for the first time, together with other previously identified isoprene tracers (i.e., 2-methyltetrols, 2-methylglyceric acid, C5-alkenetriols, and organosulfate derivatives of 2-methyltetrols). Fine ambient aerosol collected in downtown Atlanta, GA and rural Yorkville, GA during the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS) was analyzed using both gas chromatography/quadrupole mass spectrometry (GC/MS) and gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) with prior trimethylsilylation. Mass concentrations of IEPOX ranged from ~1 to 24 ng m^(−3) in the aerosol collected from the two sites. Detection of particle-phase IEPOX in the AMIGAS samples supports recent laboratory results that gas-phase IEPOX produced from the photooxidation of isoprene under low-NO_x conditions is a key precursor of ambient isoprene secondary organic aerosol (SOA) formation. On average, the sum of the mass concentrations of IEPOX and the measured isoprene SOA tracers accounted for about 3% of the organic carbon, demonstrating the significance of isoprene oxidation to the formation of ambient aerosol in this region

Nanoelectromechanical Resonator Arrays for Ultrafast, Gas-Phase Chromatographic Chemical Analysis

Miniaturized gas chromatography (GC) systems can provide fast, quantitative analysis of chemical vapors in an ultrasmall package. We describe a chemical sensor technology based on resonant nanoelectromechanical systems (NEMS) mass detectors that provides the speed, sensitivity, specificity, and size required by the microscale GC paradigm. Such NEMS sensors have demonstrated detection of subparts per billion (ppb) concentrations of a phosphonate analyte. By combining two channels of NEMS detection with an ultrafast GC front-end, chromatographic analysis of 13 chemicals was performed within a 5 s time window

Comparison of GC and HPLC for quantification of organic acids in two jaboticaba (Myrciaria) fruit varieties

Gas chromatography (GC) with trimethylsilyl derivative formation was compared to high-performance liquid chromatography (HPLC) for quantification of organic acids (OAs) in two jaboticaba (Myrciaria) fruit (pulp and pericarp) varieties (Sabará and Açu Paulista). Succinic and citric acids were the major OAs found in all the samples analyzed. Besides being much more tedious, the results obtained with GC were significantly lower than HPLC (p<0.05) when the data (acids, variety, two parts and flowering days) were considered together. The presence of both acids was confirmed by gas chromatography-mass spectrometry (GC-MS)

Using EGA-GC to Analyze Nicotine N-oxide in Order to Explain Low Nicotine Concentrations in E-cigarette Liquids

Evolved-gas analysis coupled with gas chromatography (EGA-GC) was used to analyze e-cigarette liquids. Previous analyses of e-cigarette liquids have shown that the determined concentration of nicotine is lower than the advertised concentration. A possible explanation for this phenomenon is that the nicotine in the liquids is being oxidized to nicotine N-oxide by exposure to air and thus reducing the concentration of nicotine. This study focused on analyzing samples of thermally-rearranged nicotine N-oxide. Using EGA-GC, a calibration curve was generated for nicotine N-oxide concentration, which could potentially be used to explain reduced nicotine concentrations in e-cigarette liquids