Spectrometry gas—liquid chromatography

Techniques for analysis of different mercury species in biological samples and abiotic materials include atomic absorption, cold vapor atomic fluorescence spectrometry, gas-liquid chromatography with electron capture detection, and inductively coupled plasma mass spectrometry (Lansens etal. 1991 Schintu etal. 1992 Porcella etal. 1995). Methylmercury concentrations in marine biological tissues are detected at concentrations as low as 10 pg Hg/kg tissue using graphite furnace sample preparation techniques and atomic absorption spectrometry (Schintu et al. 1992). 

Very little in the way of advances has occurred since 1971 in the applications of ultraviolet or infrared spectroscopy to the analysis of fluonnated organic compounds Therefore, only gas-liquid chromatography, liquid chromatography, mass spectrometry, and electron scattering for chemical analysis (ESCA) are discussed The application of nuclear magnetic resonance (NMR) spectroscopy to the analysis of fluonnated organic compounds is the subject of another section of this chapter... 

The active drug and metabolites can be detected from the urine by thin-layer chromatography, gas-liquid chromatography, or gas chromatography-mass spectrometry. However, assays are available only at specialized centers. Treatment of acute intoxication with mescaline is virtually identical to the treatment outlined for LSD intoxication. DOM-induced vasospasm responds well to intra-arterial tolazohne or sodium nitroprusside. Major life-threatening complications of hallucinogenic amphetamine derivatives include hyperthermia, hypertension, convulsions, cardiovascular collapse, and self-inflicted trauma. 

All of the above lipids can be separated from one another by techniques such as column, thin layer, and gas-liquid chromatography and their strucmres established by mass spectrometry. 

The structures of many oligosaccharide chains can be elucidated by gas-liquid chromatography, mass spectrometry, and high-resolution NMR spectrometry. Glycosidases hydrolyze specific linkages in oligosaccharides and are used to explore both the structures and functions of glycoproteins. 

Defaye, K. and Garcia Fernandez, J.M., Protonic and thermal activation of sucrose an the oligosaccaride composition of caramel. Carbohydrate Res., 256, Cl, 1994. Ratsimba, V. et al.. Qualitative and qnantitative evaluation of mono- and disaccharides in D-fructose, D-glucose and sucrose caramels by gas-liquid chromatography-mass spectrometry di-D-fructose dianhydrides as tracers of caramel authenticity, J. Chro-matogr. A, 844, 283, 1999. 

GABA, heterocyclic analogues, 22 (1985) 67 GABAa receptor ligands, 36 (1999) 169 Gas-liquid chromatography and mass spectrometry, 12 (1975) 1 Gastric H /K -ATPase inhibitors, 31 (1994) 233... 

This procedure was compared with sequential extractive techniques employing alkaline hydrolysis of dried plant tissue followed by extraction of the acidified mixture with ethyl acetate. Fractions were individually evaluated for phytotoxic properties. Selected fractions from those showing a positive response were analyzed by gas-liquid chromatography. Structural identification and characterization of the individual components in these selected fractions were accomplished by gas chromatography-mass spectrometry. 

Spiroaziridinium compounds have also been synthesized under photochemical conditions. For example, the photolysis of piperidine 83 in acetonitrile resulted in 3-azoniaspirooctane 85 (Equation 19) <1997JOC6903>. Its presence was detected by H NMR spectroscopy and mass spectrometry. This azoniaspiro species was thought to be transient and went on to form N-substituted piperidines which were qualitatively identified by gas liquid chromatography (GLC). 

Meier Augenstein, W., Watt, P. W. and Langhans, C. D. (1996) Influence of gas chromatographic parameters on the measurement of 13C/12C isotope ratios by gas liquid chromatography combustion isotope ratio mass spectrometry. I. Journal of Chromatography, A 752, 233 241. 

Over the past two decades, capillary electrophoresis (CE) and related techniques have rapidly developed for the separation of a wide range of analytes, ranging from large protein molecules to small inorganic ions. Gas chromatography has been considered as a powerful tool due to its sensitivity and selectivity, especially when coupled with mass spectrometry. Nevertheless, liquid chromatography is the most used method to separate and analyze phenolic compounds in plant and tissue samples. 

Wade and Quinn [12] measured the hydrocarbon content of sea surface and subsurface samples. Hydrocarbons were extracted from the samples and analysed by thin-layer and gas-liquid chromatography. The hydrocarbon content of the surface micro layer samples ranged from 14 to 599 pg/1 with an average of 155 pg/1, and the concentration in the subsurface samples ranged from 13 to 239 pg/1 and averaged 73 pg/1. Several isolated hydrocarbon fractions were analysed by infrared spectrometry and each fraction was found to contain a minimum of 95% hydrocarbon material, including both alkenes and aromatics. 

WATSON, D.G., PITT, A.R., Analysis of flavonoids in tablets and urine by gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry, Rapid Comm. Mass Spectrom., 1998,12,153-156. 

ECD = electron capture detector GC = gas chromatography GLC = gas liquid chromatography MS = mass spectrometry... 

J. N. Damico and R. P. Barron. Application of Field Ionization to Gas-Liquid Chromatography-Mass Spectrometry (GLC-MS) Studies. Anal. Chem., 43(1971) 17-21. 

GABA, heterocyclic analogues, 22 (1985) 67 Gas-liquid chromatography and mass spectrometry, 12 (1975) 1... 

Note. Abbreviations g.l.c., gas-liquid chromatography e.i.-m.s., electron-impact mass spectrometry c.i.-m.s., chemical-ionization mass spectrometry h.p.l.c., high-performance liquid chromatography h.p.a.e., high pH anion-exchange f.a.b.-m.s., fast-atom-bombardment mass spectrometry l.s.i.-m.s., liquid secondary-ion mass spectrometry n.O.e., nuclear Overhauser enhancement. Details of these methodologies are given in Ref. (3). 

Bay, Massachusetts. Gas liquid chromatography was used to detect hydrocarbons present at different depths in the sediment, while low resolution mass spectrometry was employed to measure concentrations of paraffins, cycloparaffins, aromatics and polynuclear aromatics. Their data show that the concentrations of total and saturated hydrocarbons decreased with increased depth, and it was noted that identification and quantification of hydrocarbons in oil-contaminated sediments is required if the fate of these compounds in dredge spills is to be determined. 

Oswald EO, Albro PW, McKinney JD. 1974. Utilization of gas-liquid chromatography coupled with chemical ionization and electron impact mass spectrometry for the investigation of potentially hazardous environmental agents and their metabolites. J Chromatogr 98(2) 363-448. 

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