Combined gas chromatography-mass

McFadden, W.H., Techniques of Combined Gas Chromatography/Mass Spectrometry, Wiley, New York, 1973. McLafferty, F.W., Tandem Mass Spectrometry, Wiley, New York, 1983. 

Deuterium exchange of conjugated enones and dienones on pretreated gas chromatography columns has been found useful for the characterization of these compounds by combined gas chromatography-mass spectrometry. ... 

Combined Gas Chromatography—Mass Spectrometry Applications in Organic Analysis , Wiley-Interscience, NY (1973) 65) C.S. 

Drucker, D. B. Jenkins, S. A. Applications of mass spectrometry including combined gas chromatography-mass spectrometry in taxonomic studies of bacteria. Biochem. Soc. Trans. 1989,17, 245-249. 

The potential for the preservation of lipids is relatively high since by definition they are hydrophobic and not susceptible to hydrolysis by water, unlike most amino acids and DNA. A wide range of fatty acids, sterols, acylglycerols, and wax esters have been identified in visible surface debris on pottery fragments or as residues absorbed into the permeable ceramic matrix. Isolation of lipids from these matrices is achieved by solvent extraction of powdered samples and analysis is often by the powerful and sensitive technique of combined gas chromatography-mass spectrometry (GC-MS see Section 8.4). This approach has been successfully used for the identification of ancient lipid residues, contributing to the study of artifact... 

Methods have been described for determining chlorinated aliphatic hydrocarbons in soil and chemical waste disposal site samples. The latter method involves a simple hexane extraction and temperature programmed gas chromatographic analysis using electron capture detection and high resolution glass capillary columns. Combined gas chromatography-mass spectrometry was used to confirm the presence of the chlorocarbons in the samples [4],... 

Evershed RP, Combined gas chromatography-mass spectrometry. Gas Chromatography 359—391, 1993. 

The polymerization was also terminated with CH3OH or CH3OD in the case to detect butane. From the volatile fraction distilled out from the reaction mixture on a vacuum line, low-boiling compounds were collected by redistillation and subjected to the analysis by combined gas chromatography-mass spectrometry. Butane (BuH) and monodeuterated butane, CH3CH2CH2CH2D (BuD), employed as authentic samples, were obtained by the reaction of BuLi with CH3OH and CH3OD, respectively. 

Ranid instrumental techniques were used to elucidate off-flavor problems in raw and processed rice products, raw and roasted peanuts, and corn-soy food blends. Less than a gram of the solid material was secured in a standard or special injection port liner of the gas chromatograph. Then, the volatiles from the sample were steam distilled in situ and identified by combined gas chromatography/mass spectrometry. 

This chapter provides some insight into the chemistry of a number of commonly used polymeric sorbents. Particular focus is placed on the chemical identification of contaminants typically associated with each of the following types of polymeric sorbents Amberlite XAD resins, Ambersorb XE resins, and PUF. Emphasis is placed on the chemical speciation of solvent-extractable organic contaminants present in a number of these sorbents as received from the manufacturer. Both qualitative and quantitative data on a micrograms-per-gram (parts-per-million) basis are provided as determined by combined gas chromatography-mass spectrometry (GC-MS). 

W. McFadden, Techniques of Combined Gas Chromatography/Mass Spectrometry, Wiley-lnterscience, New York, 1973. 

Both the liquid and gas products were analyzed by gas chromatography. The column for the liquid analysis was 20% Apiezon L on 60-80 mesh Chromosorb P. The column measured 1/4 inch by 7 feet. The gas analysis utilized a 1/4 inch by 10 foot column of 60-80 mesh Chromosorb 102. Temperature programming was required in both analyses. Identification of the GC peaks was based on retention time of pure compounds when these were available. In addition, two of the samples were analyzed by combined gas chromatography-mass spectrometry. By comparing the observed mass spectrometer fragmentation patterns with tabulated patterns it was possible to identify virtually every component in the product. Further details are available in the theses by Wu (23) and Early (J+). 

The relationship between structure and paper-chromatographic mobility of aldono-1,4-lactones has been discussed.65 Butanone, saturated with water, is suitable for the preparative separation of lactones on cellulose columns free acids and reducing sugars move very slowly in this system. Separation of aldono-1,4-lactones and of aldonic acids as their O-(trimethylsilyl) derivatives has been accomplished.66 The mass spectra of such derivatives are characteristic, so that it is possible to identify aldonic acids67 and lactones68 by means of combined gas chromatography-mass spectrometry. 

Compound identifications were made by combined gas chromatography-mass spectrometry (GC-MS) based on relative retention times and mass spectral interpretations. The instrument used was a Finnigan 5100 computerized GC-MS system equipped with a 50 m x 0.32 mm i.d. fused silica capillary coated with CP Sil 8 CB (0.25 jim film thickness). Helium was used as carrier gas and the temperature program was as follows 110°C (2 min)- 3°C/min - 320°C. 

The most conclusive method to identify ABA is by combined gas chromatography-mass spectrometry (20, 29, 33). Little et al. (34) monitored the current of a single ion, viz, that of the base peak, m/e 190, in the mass spectrum of Me-ABA, for quantitative determinations of ABA in the cambium of Picea sitchensis. However, few laboratories are able to carry out... 

It is obvious that unequivocal identification of small quantities of ABA can only be accomplished by combined gas chromatography-mass spectrometry. However, once this has been accomplished in a particular system, routine measurements will in the future probably mostly rely on gas chromatography with electron capture detector and on radioimmunoassay. 

Buser HR, Bosshardt HP. 1976. Determination of polychlorinated dibenzo-p-dioxins and dibenzofiirans in commercial pentachlorophenols by combined gas chromatography-mass spectrometry. J Assoc Off Anal Chem 59 562-569. 

In the past several decades the use of combined gas chromatography - mass spectrometry (6C-MS) has produced quantum leaps in the science of flavor chemistry. 

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