Hybrids, mass spectrometry

De Jong APJ, Liem AKD, Den Boer AC, et al. 1989. Analysis of polychlorinated dibenzofurans and dibenzo-p-dioxins in human milk by tandem hybrid mass spectrometry. Chemosphere 19 59-66. 

Miyaguchi H, Inoue H (2011) Determination of amphetamine-type stimulants, cocaine and ketamine in human hair by liquid chromatography/linear ion trap-Orbitrap hybrid mass spectrometry. Analyst 136(17) 3503—3511. doi 10.1039/c0an00850h... 

Mauriala T, Chauret N, Oballa R, Nicoll-Griffith DA, Bateman KP. A strategy for identification of drug metabolites from dried blood spots using triple-quadrupole/ linear ion trap hybrid mass spectrometry. Rapid Commun Mass Spectrom 2005 19 1984-1992. 

Keywords Data mining Deconvolution software Degradation products Emerging contaminants High resolution mass spectrometry system Hybrid mass spectrometry system Metabolites Non-target analysis Screening analysis Transformation products Surface water UHPLC Unknown compounds... 

For stand-alone or hybrid TOF mass spectrometry, the ions examined must all start from some point at the same instant. From this zero time, the ions are accelerated through a short region by applying a short pulse of electric potential of several kilovolts. The acceleration gives the ions velocities that vary in proportion to the square root of their m/z values. 

Hofmann elimination of, 936-938 hybrid orbitals in, 19 hydrogen bonding in. 920 IR spectroscopy of, 428, 952 mass spectrometry of, 416, 954-955... 

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. 

As another example, the tropylium ion [3 ], which is stabilized by virtue of the 67t electrons spread over a heptagonal sp hybridized carbon framework [Hiickel s (4n 4- 2)v rule with = 1], is also unstable in the gas phase. Its formation from toluene or the benzyl cation has been a long-standing problem in organic mass spectrometry, and the reaction mechanism and energetics have recently been exhaustively discussed (Lif-shitz, 1994). It was, however, isolated as the bromide salt by Doering and Knox (1954, 1957), and was the first non-benzenoid aromatic carbocation. 

Mazzuca, P. et al.. Mass spectrometry in the study of anthocyanins and their derivatives differentiation of Vitis vinifera and hybrid grapes by liquid chromatogra-phy/electrospray ionization mass spectrometry and tandem mass spectrometry, J. Mass Spectrom., 40, 83, 2005. 

Fast atom bombardment (FAB) Plasma desorption (PD) Liquid secondary-ion mass spectrometry (LSIMS) Thermospray (TSP)/plasmaspray (PSP) Electrohydrodynamic ionisation (EHI) Multiphoton ionisation (MPI) Atmospheric pressure chemical ionisation (APCI) Electrospray ionisation (ESI) Ion spray (ISP) Matrix-assisted laser desorption/ionisation (MALDI) Atmospheric pressure photoionisation (APPI) Triple quadrupole (QQQ) Four sector (EBEB) Hybrid (EBQQ) Hybrid (EB-ToF, Q-ToF) Tandem ToF-ToF Photomultiplier... 

In mass spectrometers, ions are analysed according to the ml7. (mass-to-charge) value and not to the mass. While there are many possible combinations of technologies associated with a mass-spectrometry experiment, relatively few forms of mass analysis predominate. They include linear multipoles, such as the quadrupole mass filter, time-of-flight mass spectrometry, ion trapping forms of mass spectrometry, including the quadrupole ion trap and Fourier-transform ion-cyclotron resonance, and sector mass spectrometry. Hybrid instruments intend to combine the strengths of the component analysers. 

Instrumental developments concern micro ion traps (sub-mm i.d.) [193], extension of the mass range, mass resolution and capture efficiency for ions generated externally. Fast separations at very low detection levels are possible by means of hybrid QIT/reToF mass spectrometry [194]. 

LC-tandem mass spectrometry Bacterial 2-hybrid system... 

The difficulty with protein arrays is that proteins do not behave as uniformly as nucleic acid. Protein function is dependent on a precise, and fragile, three-dimensional structure that may be difficult to maintain in an array format. In addition, the strength and stability of interactions between proteins are not nearly as standardized as nucleic acid hybridization. Each protein-protein interaction is unique and could assume a wide range of affinities. Currently, protein expression mapping is performed almost exclusively by two-dimensional electrophoresis and mass spectrometry. The development of protein arrays, however, could provide another powerful... 

The experiments described above indicate that technology is available to couple SPR with mass spectrometry. These methods should be useful for protein-protein interaction mapping. For example, immobilized proteins can be used as hooks for fishing binding partners from complex protein mixtures under native conditions. The coupling of techniques can lead not only to the rapid identification of interacting proteins but will also provide information on the kinetic parameters of the interaction. This approach should serve as an excellent complement to the use of in vivo techniques such as the yeast two-hybrid system. 

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