Spectrometry, mass and selected ion monitoring

Quantitation Using Cl Mass Spectrometry and Selected Ion Monitoring. 

In normal human liver (7 samples) identified bile acids were cholate (54%), chenodeoxycholate (28%), and deoxycholate (18%) [12]. With a more sensitive system of analysis (glass capillary gas chromatography-mass spectrometry and selected ion monitoring) the values reported for 5 bile acids from 10 samples of normal human bile [14] were cholate (41%), chenodeoxycholate (39%), deoxycholate (15%), ursodeoxycholate (4%), and lithocholate (1%). 

Wolfensberger M., Redweik U, and Curtius H. Ch (1979) Gas chromatography-mass spectrometry and selected ion monitoring of the N,N -dipentafluoropropionylhexafluoroisopropyl ester of glutamine. / Chromatogr 172, 471-475. 

Field ionization mass spectrometry and selected ion monitoring, 143... 

Solid-phase microextraction (SPME) was used for headspace sampling. The FFA were extracted from the headspace with PA, Car/PDMS, and CW/DVB fibers. It was examined whether addition of salt (NaCl) and decreasing the pH by addition of sulphuric acid (H SO ) increased the sensitivity. FFA were analyzed using gas chromatography coupled to mass spectrometry in selected ion monitoring. 

Figure 5.8 Electrospray and transformed electrospray spectra of the light- and heavy-chain antibody fragments of recombinant ritnximab obtained by LC-MS analysis. Reprinted from 7. Chromatogr., A, 913, Wan, H. Z., Kaneshiro, S., Frenz, J. and Cacia, J., Rapid method for monitoring galactosylation levels dnring recombinant antibody production by electrospray mass spectrometry with selective-ion monitoring , 437-446, Copyright (2001), with permission from Elsevier Science.

Figure 5.67 Reconstructed ion chromatograms for Idoxifene and internal standard (ds-Idoxifene using LC-ToF-MS for (a) double-blank human plasma extract, (b) extract of blank human plasma containing internal standard (IS), and (c) control-blank human plasma spiked with Idoxifene at 5 gml , the LOQ of the method. Reprinted from 7. Chromatogr., B, 757, Comparison between liquid chromatography-time-of-flight mass spectrometry and selected-reaction monitoring liquid chromatography-mass spectrometry for quantitative determination of Idoxifene in human plasma , Zhang, H. and Henion, J., 151-159, Copyright (2001), with permission from Elsevier Science.

Here is a student procedure to measure nicotine in urine. A 1.00-mL sample of biological fluid was placed in a 12-mL vial containing 0.7 g Na2CO , powder. After 5.00 pig of the internal standard 5-aminoquinoline were injected, the vial was capped with a Teflon-coated silicone rubber septum. The vial was heated to 80°C for 20 min and then a solid-phase microextraction needle was passed through the septum and left in the headspace for 5.00 min. The fiber was retracted and inserted into a gas chromatograph. Volatile substances were desorbed from the fiber at 250°C for 9.5 min in the injection port while the column was at 60°C. The column temperature was then raised to 260°C at 25°C/min and eluate was monitored by electron ionization mass spectrometry with selected ion monitoring at m/z 84 for nicotine and m/z 144 for internal standard. Calibration data from replicate... 

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. 

Herron, W. J. Eadie, J. Penman, A. D. 1995. Estimation of ranolazine and eleven phase I metabolites in human plasma by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry with selected-ion monitoring. J. Chromatogr. A, 712,55-60. 

No matter which ionization technique or chromatographic method is used, three acquisition modes exist scanning, selected-ion monitoring (SIM) (not to be mistaken with SIMS, which means secondary ion mass spectrometry) and selected-reaction monitoring (SRM). 

Whiton, R. S., Lau, P., Morgan, S. L., Gilbart, J., and Fox, A. (1985). Modifications in the alditol acetate method for analysis of muramic acid and other neutral and amino sugars by capillary gas chromatography-mass spectrometry with selected ion monitoring. /. Chromatogr. A 347, 109—120. 

Dehennin L. Estradiol-17 beta determined in plasma by gas chromatography-mass spectrometry with selected ion monitoring of mixed silyl ether-perfluoroacyl ester derivatives and use of various stable-isotope-iabeled internal standards. Clin Chem 1989 35 532-6. 

D. Robertson, E.C. Heath, EC. Falkner, R.E. Hill, G.M. Brillis and J.T. Watson, A selective and sensitive assay for urinary metanephrine and normetanephrine using gas chromatography-mass spectrometry with selected ion monitoring. Biomed. Mass Spectrom., 5, 704-708 (1978). 

K. M. Eehlberg Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory Determination of pesticides in water by C-18 solid-phase extraction and capillary-column gas chromatography/ mass spectrometry with selected-ion monitoring U.S. Geological Survey Open-Eile Report 95-181, Denver, CO (1995) 49. 

Assay methods using combined gas chromatography-mass spectrometry with selected ion monitoring and addition of stable isotopes as carriers and internal standards have been published for the different HETE isomers [208,236,385]. However, so far no GC-MS-assay for LTB4 and related dihydroxy acids or the cysteinyl-containing leukotrienes have been described. Deuterated standards of HETEs were prepared from octadeuterated arachidonic acid either by biosynthesis in mammalian tissues [236,385] or by chemical methods [208]. Preparation of internal standards by chemical methods resulted in deuterated standards with minimal contamination of unlabeled material. This resulted in assays with a detection limit of about 1 pmol for the different HETEs. A GC-MS assay without addition of deuterated internal standards has also been described for analysis of the ratio between different HETEs in the same sample [210]. 

Distillation. Essential Oils. Extraction Solvent Extraction Principles Solid-Phase Extraction Solid-Phase Microextraction. Gas Chromatography Detectors Mass Spectrometry Chiral Separations. Headspace Analysis Static Purge and Trap. Mass Spectrometry Principles Selected Ion Monitoring. Quality Assurance Quality Control. Sensors Overview. 

MLcroassay for Primadone and Its Metabolites Phenylethylmalondiamine Phenobarbital and p-Hydroxypheno-barbital in Human Serum, Saliva, Breast Milk and Tissue by Gas Chromatography-Mass Spectrometry Using Selected Ion Monitoring J. Chromatogr. 182(1) 71-79 (1980) ... 

A Selective and Sensitive Assay for Urinary Metanephrine and Normeta-nephrine Using Gas Chromatography-Mass Spectrometry with Selected Ion Monitoring... 

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