Gas chromatograph mass spectrometry GC-MS

Supersonic gas chromatograph-mass spectrometry (GC-MS) apparently has several advantages over standard GS-MS methods for the detection of thermally unstable molecules <2004JCH233>. A GC and MS are interfaced with a supersonic molecular beam (SMB), and activation of cold compounds in the SMB occurs by electron ionization or cluster chemical ionization. The gas flow rate is very high, permitting the elution of compounds that would normally be degraded. Ethylene sulfone was one of the analytes for which the technique was demonstrated. 

Although anhydrous mustard is not a substantial corrosion threat to most metals, hydrolysis forms hydrochloric acid and does contribute to mustard s corrosive behavior. An interesting pmr and gas chromatograph-mass spectrometry (GC-MS) study of the hydrolysis of HD has been reported (Logan and Sartori, 2003). In this work, it was shown that hydrolysis (D2O at 22°C) had a half-life of approximately 7 min, but that in the presence of sodium chloride, the half-life increased to approximately 24 min. These results are consistent with those reported by Bartlett and Swain (1949). 

Gas chromatographic/mass spectrometry (GC/MS) results were obtained at the Ohio State University Chemical Instrumentation Center using a Finnigan 4021 GC/MS instrument. Both electron impact and chemical ionization were performed on samples following separation of compounds by a gas chromatograph equipped with capillary columns containing 3% 0V-17 or 5% carbowax 20M. 

A gas chromatographic-mass spectrometry (GC-MS) technique is described for the detection and identification of anabolic steroid drugs in urine samples of athletes competing in major international events. 

When the gas chromatograph is attached to a mass spectrometer, a very powerful analytical tool (gas chromatography-mass spectrometry, GC-MS) is produced. Vapour gas chromatography allows the analyses of mixtures but does not allow the definitive identification of unknown substances whereas mass spectrometry is good for the identification of a single compound but is less than ideal for the identification of mixtures of... 

In gas chromatography/mass spectrometry (GC/MS), the effluent from a gas chromatograph is passed into a mass spectrometer and a mass spectrum is taken every few milliseconds. Thus gas chromatography is used to separate a mixture, and mass spectrometry used to analyze it. GC/MS is a very powerful analytical technique. One of its more visible applications involves the testing of athletes for steroids, stimulants, and other performance-enhancing drugs. These drugs are converted in the body to derivatives called metabolites, which are then excreted in the... 

Gas chromatography/mass spectrometry (GC/MS) is the synergistic combination of two powerful analytic techniques. The gas chromatograph separates the components of a mixture in time, and the mass spectrometer provides information that aids in the structural identification of each component. The gas chromatograph, the mass spectrometer, and the interface linking these two instruments are described in this chapter. 

To determine the residue levels of dinitroaniline herbicides, GC/NPD or GC/ECD is used in general. An aliquot of GC-ready sample solution is injected into the gas chromatograph under the conditions outlined below. Further confirmatory analysis is carried out using gas chromatography/mass spectrometry (GC/MS) in the selected-ion monitoring (SIM) mode. 

Gas chromatograph injector liner [for gas chromatography/mass spectrometry (GC/MS)], cyclo-double gooseneck, 2 mm, Restek (cat. No. 20907)... 

Gas chromatography/mass spectrometry (GC/MS) Gas chromatograph equipped with a split/splitless injector, autosampler, DB-5 MS fused-silica column, 15 m x 0.25-mm i.d., 0.25-qm film thickness and mass-selective detector... 

Once into the 21st century, hyphenated instrumentation (i.e., those that couple two instruments together) became prevalent in laboratories. This is the combination of two or more, often different, instruments. In simple terms, the purpose is to first separate the analyte of interest and then to identify it. This takes place using a sample injected into the combined instruments. The most common of the hyphenated instruments is the gas chromatograph, the output of which is fed into a mass spectrometer to produce a gas chromatography-mass spectrometry (GC-MS) [35],... 

Reliable identification of explosives in a modem forensic laboratory is based on instmmental techniques, mainly spectrometric, often in conjunction with chromatographic methods. Gas chromatography—mass spectrometry (GC/MS) is considered to be an excellent and reliable method in forensic analysis, including the analysis of explosives. 

Tokusoglu O, Unal MK, Yemis F. 2005. Determination of the phytoalexin resveratrol (3,5,4 -trihydroxystilbene) in peanuts and pistachios by high-performance liquid chromatographic diode array (HPLC-DAD) and gas chromatography-mass spectrometry (GC-MS). J Agric Food Chem 53 5003-5009. 

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