Liquid chromatography/mass spectrometry analytes

Dohta, Y, Yamashita, T, Horiike, S., Nakamura, T. and Kukami, T. (2007) A system for logD screening of 96-weIl plates using a water-plug aspiration/ injection method combined with high-performance liquid chromatography-mass spectrometry. Analytical Chemistry, 79, 8312-8315. 

Lindsey M.E., M. Meyer, and E.M. Thurman (2001). Analysis of trace levels of sulfonamide and tetracycline antimicrobials in groundwater and surface water using solid-phase extraction and liquid chromatography/mass spectrometry. Analytical Chemistry 73 4640-4646. 

Tanabe, A. and K. Kawata (2004). Determination of triazine pesticides and related compounds in environmental water by liquid chromatography-mass spectrometry. Analyt. Sci., 20 227-230. 

Robb DB, Covey TR, Bruins AP (2000) Atmospheric Pressure Photoionization An Ionization Method for Liquid Chromatography-Mass Spectrometry. Analytical Chemistry 72 3653-3659... 

Rosenberg, E. (2008) Characterisation of historical organic dyestuffs by liquid chromatography-mass spectrometry. Analytical and Bioanalyticcd Chemistry, 391, 33-57. 

Hart, D.J., Finglas, P.M., Wolfe, C.A., Mellon, F., Wright, A.J.A., and Southon, S., 2002. Determination of 5-methyltetrahydrofolate (13C-labeled and unlabeled) in human plasma and urine by combined liquid chromatography mass spectrometry. Analytical Biochemistry. 305 206 213. 

Pawlosky, R.J., Flanagan, V.P., and Pfeiffer, C.M., 2001. Determination of 5-methyltetrahydrofolic acid in human serum by stable-isotope dilution high-performance liquid chromatography-mass spectrometry. Analytical Biochemistry. 298 299-305. 

Ruhaak, L. R. Deelder, A. M. Wuhrer, M. OUgosaccharide analysis hy graphitized carbon liquid chromatography-mass spectrometry. Analytical and Bioanalytical Chemistry... 

Apffel, j. a., U. a. T. Brinkman, R. W. Frei, and E. A. I. M. Evers Gas-Nebulized Direct Liquid Introduction Interface for Liquid Chromatography/Mass Spectrometry. Analyt. Chemistry 55, 2280 (1983). 

Blakley CR and Vestal ML (1983) Thermospray interface for liquid chromatography/mass spectrometry. Analytical Chemistry 55 750-754. 

Liquid chromatography/mass spectrometry (LC/MS) is an analytical technique combining the advantages of an LC instrument with those of a mass spectrometer. 

During gc/ms or liquid chromatography/mass spectrometry (Ic/ms) acquisitions, it is possible to perform a mixture of the experiments described in Table 2 for different time windows, with the experimental parameters, such as the coUision energy, optimized for each analyte. 

In this book, I have tried to show the way in which high performance liquid chromatography-mass spectrometry (LC-MS) has developed, somewhat slowly it has to be said, into a powerful hybrid analytical technique. 

The method for chloroacetanilide soil metabolites in water determines concentrations of ethanesulfonic acid (ESA) and oxanilic acid (OXA) metabolites of alachlor, acetochlor, and metolachlor in surface water and groundwater samples by direct aqueous injection LC/MS/MS. After injection, compounds are separated by reversed-phase HPLC and introduced into the mass spectrometer with a TurboIonSpray atmospheric pressure ionization (API) interface. Using direct aqueous injection without prior SPE and/or concentration minimizes losses and greatly simplifies the analytical procedure. Standard addition experiments can be used to check for matrix effects. With multiple-reaction monitoring in the negative electrospray ionization mode, LC/MS/MS provides superior specificity and sensitivity compared with conventional liquid chromatography/mass spectrometry (LC/MS) or liquid chromatography/ultraviolet detection (LC/UV), and the need for a confirmatory method is eliminated. In summary,... 

The need to understand the fate of pesticides in the environment has necessitated the development of analytical methods for the determination of residues in environmental media. Adoption of methods utilizing instrumentation such as gas chro-matography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), liquid chromatography/tandem mass spectrometry (LC/MS/MS), or enzyme-linked immunosorbent assay (ELISA) has allowed the detection of minute amounts of pesticides and their degradation products in environmental samples. Sample preparation techniques such as solid-phase extraction (SPE), accelerated solvent extraction (ASE), or solid-phase microextraction (SPME) have also been important in the development of more reliable and sensitive analytical methods. 

For method tryout, run a control sample and two fortifications from each site. One fortification should be done at the LOQ and the other at the highest expected residue level, perhaps 1000 x LOQ. If the recoveries are within the acceptable range of 70-120% and there are no interferences, proceed with the method validation. If interferences are present which prevent quantitation of the analyte, try additional cleanup steps with SPE or use a more selective detection method such as liquid chromatography/mass spectrometry (LC/MS). 

Maynard, D.M., Masuda, J., Yang, X., Kowalak, J.A., Markey, S.P. (2004). Characterizing complex peptide mixtures using a multi-dimensional liquid chromatography-mass spectrometry system Saccharomyces cerevisiae as a model system. J. Chromatogr. B Analyt. Technol. Biomed. Life Sci. 810, 69-76. 

B. Ardrey, Liquid Chromatography Mass Spectrometry An Introduction, AnTS Analytical Techniques in the Sciences, John Wiley Sons, Ltd, Chichester, 2003. 

C.J. Miles, D.R. Doerge and S. Bajic, Particle beam liquid chromatography-mass spectrometry of national pesticide survey analytes, Archives Environmental Contamination Toxicol., 22 (1992) 247-251. 

Nowadays, ESI is the leading member of the group of atmospheric pressure ionization (API) methods and the method of choice for liquid chromatography-mass spectrometry coupling (LC-MS, Chap. 12). [10-13] Currently, ESI and MALDI (Chap. 10) are the most commonly employed ionization methods and they opened doors to the widespread biological and biomedical application of mass spectrometry. [5,10,11,13-17] Moreover, ESI serves well for the analysis of ionic metal complexes [18,19] and other inorganic analytes. [20-22]... 

Budde, W.L. Analytical Mass Spectrometry ACS and Oxford University Press Washington, D.C. and Oxford, 2001. Current Practice of Liquid Chromatography-Mass Spectrometry Niessen,... 

The year 2002 was an extraordinary year for liquid chromatography-mass spectrometry (LC/MS) practitioners. On October 9, 2002, the Royal Swedish Academy of Sciences annonnced their decision to award the Nobel Prize in Chemistry to John B. Fenn, Koichi Tanaka, and Kurt Wiithrich for their development of analytical methods for the identification and structnral analysis of biological macromolecnles. Fenn and Tanaka shared the prize for developing electrospray and soft-laser desorption, respectively. These soft-ionization techniqnes allow macromolecules to be ionized withont fragmentation. 

Important progress in terms of higher throughput in ADME/PK work was realized recently by wider use of liquid chromatography/mass spectrometry (LC/MS), which has now become a standard analytical tool [26]. Flow NMR spectroscopy has become a routine method to resolve and identify mixtures of compounds and has found applications in drug metabolism and toxicology studies [27]. 

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