Fragmentography, mass

Selected-ion monitoring (SIM). Describes the operation of a mass spectrometer in which the ion currents at one (or several) selected m/z values are recorded, rather than the entire mass spectrum. The use of the terms multiple-ion detection (MID), multiple-ion (peak) monitoring (MPM), and mass fragmentography are not recommended. 

Cole WJ, Mitchell RG, Salamonsen RF. 1975. Isolation, characterization and quantitation of chloral hydrate as a transient metabolite of trichloroethylene in man using electron gas capture gas chromatography and mass fragmentography. J Pharm Pharmacol 27 167-171. 

Shinohara, Y., Baba, S., Kasuya, Y., Absorption, metabolism, and excretion of oral testosterone in humans by mass fragmentography,... 

Wilson, J.M., Williamson, L.J., and Raisys, V.A. 1977. Simultaneous measurement of secondary and tertiary tricyclic antidepressants by GC/MS chemical ionization mass fragmentography. Clin Chem. 23 1012. 

Chemical-ionization, mass fragmentography was used for quantitative determination of variously linked monosaccharides in a study of the high-molecular-weight glycopeptide of erythrocytes.75 It appears... 

Fig. 3.—Mass Fragmentography of Methylated Neuraminic Acids. [Detection at m/e 274 A, disialosyl-lactosylceramide B, the disialosyl ganglioside isolated C, B after treatment with neuraminidase D, the fraction containing the trisialosyl ganglioside. Detection at m/e 330 E, the disialosyl ganglioside F, the trisialosyl fraction. The peaks identified are (1) the permethylated (terminal) N-acetylneuraminic acid, and (2) the 8-O-acetyl (8-O-substituted) derivative of the methylated N-acetylneuraminic acid. Conditions 1% of SE-30, at 240°. Reproduced, by permission, from Ref. 80.]...

Fig. 4.—Mass Fragmentography (m/e 161) of Methylated Hexose Derivatives from the Disialosy] Ganglioside. [Top, before treatment with neuraminidase bottom, after treatment with Vibrio cholerae neuraminidase. The methylated hexose derivatives identified are (A) 2,4,6-tri-O-methylgalactose (B) 2,3,6-tri-O-methylglucose (C) 2,3,4,6-tetra-O-methylgalactose. The peaks eluting before C are unrelated signals that were also detected in a blank experiment employing the neuraminidase treatment. Conditions 3% of QF-1, at 190°. Reproduced, by permission, from Ref. 80.]...

Tsukioka et al. [187] determined these contact herbicides in soil by mass fragmentography. The method is based on the reaction of l-benzyl-3-p-polytriazene with an extract of Frenock and Dalapon from strongly acidified sample solutions to form benzylated species. In the analysis of soil samples, steam distillation was applied prior to extraction. Recoveries were >92% and precision <5%. 

Hashimoto Y, Miyazaki H. 1979. Simultaneous determination of endogenous norepinephrine and dopamine-beta-hyrox-ylase activity in biological materials by chemical ionization mass fragmentography. J Chromatogr 168 59. 

H4. Hammer, G.-G., Holmstedt, B., and Ryhage, R., Mass fragmentography identification of chlorpromazine and its metabolites in human blood by a new method. Anal. Biochem. 25, 532-548 (1968). 

K14. Koslow, S. H., Cattabeni, F., and Costa, E., Norepinephrine and dopamine assay by mass fragmentography in the picomole range. Science 176, 177-180 (1972). 

Uzunov DP, Cooper TB, Costa E, Gnidotti A (1996) Flnoxetine-elidted changes in brain neurosteroid content measured by negative ion mass fragmentography. Proc Natl Acad Sci USA 93 12599-12604... 

GC-MS, usually using the mass fragmentography technique (specific mass detection), is important in the analysis of mixtures containing polychloro-dibenzofurans, ... 

Kok RM, Howells DW, van den Heuvel CC, Guerand WS, Thompson GN, Jakobs C (1993) Stable isotope dilution analysis of GABA in CSF using solvent extraction and electron-capture negative-ion mass fragmentography. J Inherit Metab Dis 16 508-512... 

Costa CG, Struys EA, Bootsma A, et al (1997) Quantitative analysis of plasma acylcarnitines using gas chromatography chemical ionization mass fragmentography. J Lipid Res 38 173-182... 

Stellaard F, ten Brink HJ, Kok RM, van den Heuvel L, Jakobs C (1990) Stable isotope dilution analysis of very long chain fatty acids in plasma, urine and amniotic fluid by electron capture negative ion mass fragmentography. Clin Chim Acta 192 33-144... 

Stellaard F, Langelaar SA, Kok RM, Jakobs C (1989) Determination of plasma bile acids by capillary gas-liquid chromatography-electron capture negative chemical ionization mass fragmentography. J Lipid Res 30 1647-1652... 

Gas Chromatography-Mass Spectrometry. A Finnigan 4500/Incos instrument with a 30-m X 0.32-mm i.d. capillary column coated with SP-B-5 was used. The GC parameters were as follows injector, 270 °C column oven temperature programmed, 50 °C (0.1 min, hold) 15 °C/min to 100 °C, 5 °C/min to 270 °C internal standard, anthracene-djo helium flow, 3.0 mL/min sample size, 3.0 /xL. MS conditions were as follows El, 70 eV scan (m/z), 35-650 daltons source temperature, 250 °C filament current, 0.5 A sensitivity, 10-8 A/V. (NOTE When the name of a compound is followed by (confirmed) , it means that the standard material was analyzed for confirmation under conditions identical to those of the sample when the name is followed by (tentative) , it means that the mass fragmentography showed the best fit (>80 ) based on the National Bureau of Standards [NBS] library computer search.)... 

Frenock, sodium-2,2,3,3-tetrafluoroproprionate Steam distillation, solvent extraction Mass fragmentography of l-benzyl-3-p-polytriazine derivative [477]... 

Phenols, aromatic acids, eg pentachlorophenol, Ethyl acetate - - GC, mass -fragmentography [13]... 

Vinyl chloride Mass fragmentography then GC-MS recording m/e 62 and 64 peaks. Quadrupole m/s equipped with multiple ion detection sub pg L1 [18]... 

Geosmin, 2-methyisobomeol Computer controlled GC-mass fragmentography lOng L-1 [89]... 

Vinyl chloride - Mass fragmentography followed by GC-MS, recon. in m/e 62 and 64 peaks, (quadrupole MS with multiple ion detector) [158]... 

They generally lack sensitivity and a direct relation to molecular structure. GC-MS is fast, direct, and very sensitive, and the spectrum provides a result which puts identification beyond dispute. Computer-assisted systems are now available which embody extensive drug reference libraries and can be automatically searched to identify unknown spectra. The further development of chemical ionization and mass fragmentography methods using stable isotopes now permits very accurate quantitative work. 

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