Electrospray-Mass-Spectrometry

Tandem Mass Spectrometry Electrospray Ionization Fourier Transform -Antibody-Based Identification... 

A.T. Blades, M.G. Ikonomou and P. Kebarle, Mechanism of electrospray mass spectrometry. Electrospray as an electrochemical cell, Anal. Chem., 63 (1991) 2109-2114. 

The development of mass spectrometric ionization methods at atmospheric pressures (API), such as the atmospheric pressure chemical ionization (APCI)99 and the electrospray ionization mass spectrometry (ESI-MS)100 has made it possible to study liquid-phase solutions by mass spectrometry. Electrospray ionization mass spectrometry coupled to a micro-reactor was used to investigate radical cation chain reaction is solution101. The tris (p-bromophenyl)aminium hexachloro antimonate mediated [2 + 2] cycloaddition of trans-anethole to give l,2-bis(4-methoxyphenyl)-3,4-dimethylcyclobutane was investigated and the transient intermediates 9 + and 10 + were detected and characterized directly in the reacting solution. However, steady state conditions are necessary for the detection of reactive intermediates and therefore it is crucial that the reaction must not be complete at the moment of electrospray ionization to be able to detect the intermediates. 

The two mainstays of modem mass spectrometry, electrospray MS and MALDI/ TOFMS, can both be used with adequate sensitivity for single-bead detection of molecular weight and structural information [37], Single-bead MS using TFA cleavage and MALDI/ TOF analysis is now a well-established technique [38 11], A Scripps group [42] reports... 

Capillary Electrophoresis with Flame Photometric Detection Chemical Weapons Convention Extracted Ion Chromatogram Electron Impact Mass Spectrometry Electrospray Ionization Flow Injection Analysis Flame Photometric Detector Gas Chromatography/Fourier Transform Infrared Spectroscopy Gas Chromatography/Mass Spectrometry Gas chromatography International Union for Pure and... 

Electrospray mass spectrometry Electrospray (ES) (8) mass spectra were acquired on a Perkin-Elmer Sciex (Concord, Canada) API III triple-quadrupole mass spectrometer equipped with an atmospheric pressure nebulization-assisted electrospray (ion-spray) source (9). The ion-spray needle... 

S. Hillenkamp, F De Vries, M.S. Comparative Mass Spectrometric Analyses of Photofrin Oligomers by Fast Atom Bombardment Mass Spectrometry, UV and IR Matrix-Assisted Laser Desorption/lonization Mass Spectrometry, Electrospray Ionization Mass Spectrometry and Laser Desorption/Jet-Cooling Photoionization Mass Spectrometry, J. Mass Spectrom. 34, 661-669 (1999). Powell, K.D. Fitzgerald, M.C. Accuracy and Precision of a New H/D Exchange- and Mass Spectrometry-Based Technique for Measuring the Thermodynamic Properties of Protein-Peptide Complexes, Biochemistry 42,4962-4970 (2003). 

This section will cover the two most popular ionization techniques for analyzing proteins by mass spectrometry electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI). A brief description of five common mass spectrometers that have been coupled to these ion sources will follow. 

Jensen, B.P. et al., Investigation of the metabolic fate of 2-, 3- and 4-bromobenzoic acids in bile-duct-cannulated rats by inductively coupled plasma mass spectrometry and high-performance liquid chromatography/inductively coupled plasma mass spectrometry/ electrospray mass spectrometry, Rapid Commun. Mass Spectrom., 19, 519, 2005. 

Ostman, R, Jantti, S., Grigoras, K. et al. (2006) Capillary liquid chromatography-microchip atmospheric pressure chemical ionization-mass spectrometry. Lab Chip, 6 (7), 948-953. Chang, Y.Z., Yang, M.W. and Wang, G.J. (2005) A new mass spectrometry electrospray tip obtained via precise mechanical micromachining. Anal Bioanal Chem, 383 (1), 76-82. 

One way to identify these elusive intermediates is mass spectrometry. Electrospray allows the isolation of species of various molecular weights, (Figure 7) (Rosu et al., in preparation). These dimeric and trimeric species might be intermediates leading to the formation of the tetrameric structure. However, we cannot exclude yet that they represent dead ends in the pathway towards quadruplexes their progressive disappearance at long incubation times do not unambiguously demonstrate they are true intermediates. 

Mass spectrometry— Electrospray or MALDl-TOF—could easily distinguish a protein of this approximate mass (101 amino acids x approximately 110 d per amino acid =12 kd) that contained an extra 41 atomic mass units as a result of the substitution of a valine for a glycine residue. 

Detection of radiolabeled proteins Mass spectrometry (electrospray ionization, matrix-assisted laser desorption, ionization) Gel electrophoresis (2D polyacrylamide gel electrophoresis)... 

See also Mass Spectrometry Electrospray Matrix-Assisted Laser Desorption/lonization Multidimensional. Polymerase Chain Reaction. 

Adding aUcaU metal iodide salts as templates induced modest changes in product distribution [36]. The most significant shift in library composition was induced by sodium iodide, which doubled the concentration of tetramer and pentamer in the reaction mixture. Binding constants were not measured however, the relative affinities of the amplified cyclophane macrocycles for the different metal alkali were studied by electrospray ionization-mass spectrometry (electrospray ionization ESI-mass spectrometry MS), finding good agreement with the main amplification observed. The yield of cychc tetramer was increased by the addition of sodium in the cases of the MEM and di(p-methoxybenzyl) monomers, and these were found to bind sodium preferentially in the ESl-MS study [109]. 

Smith RD, Loo JA, Edmonds CG, Barinaga CJ, Udseth HR. New developments in biochemical mass spectrometry electrospray ionization. Anal Chem. 1990 62 882-99. 

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