High atmospheric pressure chemical

If a high -molecular-weight compound is being studied by LC-MS, the analyst has little choice in the ionization method to use, with atmospheric-pressure chemical ionization (APCl) being wholly inappropriate. However, when low -molecular-weight componnds are involved, both electrospray ionization and APCl are potentially of value. [Pg.242]

Reversed-phase Cig chromatography column. Keystone Scientific Betasil, 100 x 2.0-mm i.d., 5-pm particle size, 100 A, Part No. 105-701-2-CPF TSQ 7000 LC/MS/MS system with electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) interface and gradient high-performance liquid chromatography (HPLC) unit, or equivalent Vacuum manifold for use with SPE cartridges (Varian Vac Elut 10 or equivalent)... [Pg.491]

Reversed-phase high-performance liquid chromatography (HPLC) column 50 mm x 3.2-mm i.d. with Kromasil 5- um Gig packing High-performance liquid chromatograph coupled to a triple-quadrupole mass spectrometer with an atmospheric pressure chemical ionization (APCI) source Gel permeation chromatograph with a 60 mm x 25-mm i.d. column packed with Bio-Beads SX-3 (50-g)... [Pg.1169]

Homish, R. E. and Wiest, J. R., Quantitation of spectinomycin residues in bovine tissues by ion-exchange high-performance liquid chromatography with post-column derivatization and confirmation by reversed-phase high performance chromatography-atmospheric pressure chemical ionization tandem mass spectrometry, /. Chromatogr. A, 812, 123, 1998. [Pg.312]

Desai,M.J., Armstrong, D.W. (2004). Analysis of native amino acid and peptide enantiomers by high-performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry. J. Mass. Spec. 39, 177-187. [Pg.340]

For confirmatory assay, liquid chromatography-tandem mass spectrometry (LC-MS/MS) is becoming more frequently used in the analysis of OTC owing to its high sensitivity and ability. Electrospray ionization (ESI) [55-57] and atmospheric pressure chemical ionization (APCI) [41] methods combined with tandem mass spectrometry are favored because of their higher sensitivity and better reproducibility. Hamscher et al. [58] developed a method for the determination of persistent TC residues in soil fertilized with manure by HPLC tandem mass spectrometry, MS-MS, and confirmation by MS-MS-MS. Zhu et al. [59] developed an LC-tandem mass spectrometry for the analysis of common tetracyclines in water. The detection limit for oxytetracycline was 0.21 pg/L. Lykkeberg et al. [60] used LC-MS/MS for determination of oxytetracycline and its impurities EOTC, TC, ETC, ADOTC, oc-AOTC, and /i-AOTC. [Pg.111]

W.E. Neff, W.C. Byrdwell, Characterization of model triacylglycerol (triolein, trilinolein and trilinolenin) autoxidation products via high performance liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry, Journal of Chromatography A, 818, 169 186 (1998). [Pg.29]

G.A. van der Doelen, K.J. van den Berg, J.J. Boon, N. Shibayama, E.R. de la Rie, W.J.L. Genuit, Analysis of fresh triterpenoid resins and aged triterpenoid varnishes by high performance liquid chromatography atmospheric pressure chemical ionisation (tandem) mass spectrometry, Journal of Chromatography A, 809, 21 37 (1998). [Pg.33]

Figure 2.1 Mass spectrometric approach. Dl, direct inlet GC, gas chromatography HPLC, high performance liquid chromatography CZE, capillary zone electrophoresis El, electron ionization Cl, chemical ionization ESI, electrospray ionization DESI, desorption electrospray ionization APCI, atmospheric pressure chemical ionization MALDI, matrix assisted laser desorption ionization B, magnetic analyzer E, electrostatic analyzer...

Gimeno R.A. et al., 2002. Determination of polycyclic aromatic hydrocarbons and polycyclic aromatic sulfur heterocycles by high-performance liquid chromatography with fluorescence and atmospheric pressure chemical ionization mass spectrometry detection in seawater and sediment samples. J Chromatogr A 958 141. [Pg.294]

In off-line coupling of LC and MS for the analysis of surfactants in water samples, the suitability of desorption techniques such as Fast Atom Bombardment (FAB) and Desorption Chemical Ionisation was well established early on. In rapid succession, new interfaces like Atmospheric Pressure Chemical Ionisation (APCI) and Electrospray Ionisation (ESI) were applied successfully to solve a large number of analytical problems with these substance classes. In order to perform structure analysis on the metabolites and to improve sensitivity for the detection of the various surfactants and their metabolites in the environment, the use of various MS-MS techniques has also proven very useful, if not necessary, and in some cases even high-resolution MS is required. [Pg.25]

For sensitive quantification in LC-MS analysis of non-ionic surfactants, selection of suitable masses for ion monitoring is important. The nonionic surfactants easily form adducts with alkaline and other impurities present in, e.g. solvents. This may result in highly complicated mass spectra, such as shown in Fig. 4.3.1(A) (obtained with an atmospheric pressure chemical ionisation (APCI) interface) and Fig. 4.3.2 (obtained with an ESI interface). [Pg.503]

Other combinations of chromatography techniques with MS which may be useful in environmental studies are the coupling of high performance liquid chromatography (LC) with MS [84,384,504,506,530,585-593],LC with MS-MS [181, 594 - 599], LC with atmospheric pressure chemical ionization MS (LC-APCI-MS) [600], and Fourier transform infrared spectroscopy-fast atom bombardment coupled to LC-MS (FTIR-FAB-LC-MS) [514]. [Pg.79]

In atmospheric pressure chemical ionization (APCI) ion-molecule reactions occurring at atmospheric pressure are employed to generate the ions, i.e., it represents a high-pressure version of conventional chemical ionization (Cl, Chap. 7). The Cl plasma is maintained by a corona discharge between a needle and the spray chamber serving as the counter electrode. The ions are transferred into the mass analyzer by use of the same type of vacuum interface as employed in ESI. Therefore, ESI ion sources can easily be switched to APCI instead of an ESI sprayer, a unit comprising a heated pneumatic nebulizer and the spray chamber with the needle electrode are put in front of the orifice, while the atmospheric pressure-to-vacuum interface remains unchanged. [48,138]... [Pg.465]

Mottram, H. Woodbury, S.E. Evershed, R.P. Identification of Triacylglycerol Positional Isomers Present in Vegetable Oils by High Performance Liquid Chromatography/Atmospheric Pressure Chemical lonization-MS. Rapid Commun. Mass Spectrom. 1997,11, 1240-1252. [Pg.474]

Chan EC, Ho PC. 2000. High-performance liquid chromatog-raphy/atmospheric pressure chemical ionization mass spec-trometric method for the analysis of catecholamines and metanephrines in human urine. Rapid Commun Mass Spectrom 14 1959. [Pg.169]

Jones JJ, Kidwell H, Games DE. 2003. Application of atmospheric pressure chemical ionization mass spectrometry in the analysis of barbiturates by high-speed analytical countercurrent chromatography. Rapid Commun Mass Spec-trom 17 1565. [Pg.171]

Kagan M, Chlenov M, Kraml CM. 2004. Normal-phase high-performance liquid chromatographic separations using ethoxynonafluorobutane as hexane alternative. II. Liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry applications with methanol gradients. J Chromatogr A 1033 321. [Pg.171]

Karlsson AA, Michelsen P, Odham G. 1998. Molecular species of sphingomyelin determination by high-performance liquid chromatography/mass spectrometry with electrospray and high-performance liquid chromatography/tandem mass spectrometry with atmospheric pressure chemical ionization. J Mass Spectrom 33 1192. [Pg.171]

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