Gas chromatography-mass spectrometry selected ion monitoring

Tanchotikul, U., and T. C. Y. Hsieh. An improved method for quantification of 2 acetyl l pyrroline, a pop-com like aroma, in aromatic rice by high-resolution gas chromatography/ mass spectrometry/selected ion monitoring. J Agr Food Chem 1991 39(5) 944-947. 

Solid Phase MicroExtraction (SPME) is a solvent-free sample preparation method based on the adsorption of analytes directly from an aqueous sample onto a coated fused-silica fiber. Headspace SPME was used in combination with gas chromatography-mass spectrometry/ selective ion monitoring (GC/MS-SIM) to analyze for TCA in wine. 

Quantitation of the Antitumor Agent N-(Phosphonacetyl)-L-aspartic Acid in Human Plasma and Urine by Gas Chromatography-Mass Spectrometry-Selected Ion Monitoring J. Chromatogr. 182(2) 163-169 (1980) CA 93 18827e... 

Determination of Uracil and Thymine and Their Nucleosides and Nucleotides in Picomole Amounts by Gas Chromatography Mass Spectrometry Selected Ion Monitoring Biomed. Mass Spectrom. 6(5) 194-199... 

Schlemmer, F., and Davis, J. M. Quantitation of Amphetamine in Plasma and Cerebrospinal Fluid by Gas Chromatography-Mass Spectrometry-Selected Ion Monitoring Using 6-Methylphenethylamine as an Internal Standard... 

Tanchotikul, U. Hsieh, T.C.Y. An Improved Method for Quantification of 2-Acetyl-l-Pyrroline, a "Popcorn"-Like Aroma, in Aromatic Rice by High-Resolution Gas Chromatography/Mass Spectrometry/Selected Ion Monitoring. J. Agr. Food Chem. 1991, 39, 944-947. 

Chart 5.5 Chemical structures of selected base-damage products identified by gas chromatography/mass spectrometry-selective ion monitoring (CC/MS-S/M) technique [89],... 

SY Chang, TA Moore, LL Devaud, LCE Taylor, EB Hollingsworth. Analysis of rat brain dialysate by gas chromatography-high-resolution selected-ion monitoring mass spectrometry. J Chromatogr 562 111—118, 1991. 

Thumhofer, S. and Vetter, W., A gas chromatography/electron ionization-mass spectrometry-selected ion monitoring method for determining the fatty acid pattern in food after formation of fattty acid methyl esters, J. Agric. Food Chem., 53, 8896-8903, 2005. 

Figure 15.8 Multidimensional GC-MS separation of urinary acids after derivatization with methyl chloroformate (a) pre-column cliromatogram after splitless injection (h) Main-column selected ion monitoring cliromatogram (mass 84) of pyroglutamic acid methyl ester. Adapted from Journal of Chromatography, B 714, M. Heil et ai, Enantioselective multidimensional gas chromatography-mass spectrometry in the analysis of urinary organic acids , pp. 119-126, copyright 1998, with permission from Elsevier Science.

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. 

Isotope dilution gas chromatography-mass spectrometry has also been used for the determination of ppb of total chromium in seawater [181-183]. The samples were reduced to ensure Cr111 and then extracted and concentrated as tris (l,l,l-trifluoro-2,4-pentanediono) chromium (III) [(Cr(tfa)3>] into hexane. The Cr(tfa)2 mass fragments were monitored into a selected ion monitoring (SIM) mode. 

Shinohara et al. [299] have described a procedure based on gas chromatography for the determination of traces of two, three, and five-ring azarenes in seawater. The procedure is based on the concentration of the compounds on Amberlite XAD-2 resin, separation by solvent partition [300], and determination by gas chromatography-mass spectrometry with a selective ion monitor. Detection limits by the flame thermionic detector were 0.5-3.0 ng and those by gas chromatography-mass spectrometry were in the range 0.02-0.5 ng. The preferred solvent for elution from the resin was dichloromethane and the recoveries were mainly in the range 89-94%. 

Lopez-Avila et al. [36] used a stable isotope dilution gas chromatography-mass spectrometric technique to determine down to O.lppb of pentachlorophenol (also Atrazine, Diazinon and lindane) in soil. Soil samples are extracted with acetone and hexane. Analysis is performed by high-resolution gas chromatography-mass spectrometry with mass spectrometer operated in the selected ion monitoring mode. Accuracy greater than 86% and a precision better than 8% were demonstrated by use of spiked samples. 

The isotope dilution gas chromatography-mass spectrometry method described by Lopez-Avila et al. [16] and discussed in section 5.3.1.3 has been applied to the determination of Atrazine in soil. In this method known amounts of labelled Atrazine were specked into soil samples before extraction with acetone-hexane. The ratio of the naturally abundant compound and the stable-labelled isotope was determined by high-resolution gas chromatography-mass spectrometry with the mass spectrometer in the selected ion monitoring mode. Detection limits of 0.1-l.Oppb were achieved. Accuracy was >86% and precision better than 8%. 

Singh AK, Hewetson DW, Jordon KC, et a1. 1986. Analysis of organophosphorus insecticides in biological samples by selective ion monitoring gas chromatography-mass spectrometry. J Chromatogr 369 83-96. 

Table 3.1.4 Preparation of stock and working solutions for gas chromatography-mass spectrometry (GC-MS) selected ion monitoring (SIM) analysis. 2MBG 2-methylbutyrylglycine, BG butyrylglycine, DCA dicarboxylic acid, EMA ethylmalonic acid, GLUT glutaric acid, HG hexanoylglycine,...

Figure 24-21 Selected ion monitoring in gas chromatography-mass spectrometry.

Figure 24-22 Selected reaction monitoring in gas chromatography-mass spectrometry, (a) Reconstructed total ion chromatogram of extract from orange peel with electron ionization, (b) Selected reaction monitoring with the precursor ion m/z 293 selected by mass filter Q1 in Figure 22-21 and product ion m/z 264 selected by mass filter Q3. The chromatogram is a graph of intensity at m/z 264 from Q3 versus time. [Courtesy Thermo Ftnnlgan GC ana GC/MS Division, San Jose. CA.J...

Kish, J.L., E.M. Thurman, E.A. Scribner, and L.R. Zimmerman (2000). Method of analysis by the US Geological Survey Organic Geochemistry Research Group Determination of triazine and chloroacetanilide herbicides in water by solid-phase extraction and capillary column gas chromatography/mass spectrometry with selected ion monitoring USGS Open-File Report 00-385. 

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