Laser-induced desorption mass spectrometry

Fast-atom bombardment mass spectrometry (FAB-MS) has been applied to the identification of diterpenoid compounds and their oxidation products. Similarly, laser-induced desorption mass spectrometric (LDMS) techniques have been applied to the identification of natural and synthetic organic pigments in microscopic paint samples prepared as cross sections [60]. 

Sobott F, Wattenberg A, Barth HD, Bmtschy B. 1999. Ionic clathrates from aqueous solutions detected with laser induced liquid beam ionization/desorption mass spectrometry. Int J Mass Spectr 185-7 271-279. 

Land, D.P., Tai, T.-L., Lindquist, J.M., Hemminger, J.C. and Mclver, R.T. (1987). Characterization of multilayer thin films by laser-induced thermal desorption mass spectrometry. Anal. Chem. 59, 2924-2927. 

Secondary-ion mass spectrometry (SIMS) of a thin layer of nucleic acid bases deposited on a silver foil under bombardment with Ar ions at 3 kV gives intense pseudomolecular ions [M H] but practically no simple bond cleavage fragments. Another new technique is that of (pulsed) laser induced desorption (LD). When applied to nucleotide bases such as cytosine or adenine (266 nm, quadruplet neodymium laser or 347 nm, ruby laser) the technique has good detection limits, particularly for ions with a short lifetime (up to 100 nsec). The technique makes use of a time-of-flight instrument and is utilized in both modes, positive (PI) and negative ions (NI). Both bases exhibit an intense [BH]" ion. These results are similar to those obtained by Cf plasma desorption (PD). 

Finally, as concerns Pt(lll), the reaction of co-adsorbed ethene-d4 and hydrogen has been studied using a combination of laser-induced thermal desorption, mass-spectrometry and RAIRS exchange occurred above 215 K with an activation energy of 46 kJ mol this being below the point at which conversion to... 

In addition to ESI, a relative new laser desorption mass spectrometry method termed laser-induced liquid bead ion desorption mass spectrometry (LILBID-MS) has been established [12], Here, preferentially monodisperse macromolecules, especially biomolecules, dissolved in microdroplets are desorbed/ablated by a mid-IR laser into vacuum [12, 13]. Two modes of desorption are addressable an ultrasoft mode at lower laser intensity in which, for example, a macromolecule complex is desorbed into vacuum and a harsher mode at higher laser intensity by which it is dissociated into its covalent subunits. A broad range of molar masses of biohybrid stmctures and transmembrane protein complexes, etc. can be determined up to 1,000,000g/mol, as long as the to be analyzed macromolecular structures can be dissolved in water or in buffer solution with low ionic strength. With this LILBID-MS molar masses of water-soluble glycodendrimers and their complexes with inorganic Re clusters are determinable (Fig. 4.8) [14],... 

Chapter 7, titled Interfacing TLC with Laser-Based Ambient Mass Spectrometry, provides an overview of mass spectrometric techniques that can be coupled with TLC under the most convenient working conditions, that is, at room temperature and atmospheric pressure. The authors introduce readers to electrospray laser desorption ionization (ELDI), plasma-assisted multiwavelength laser desorption/ionization (PAMLDI), laser desorption atmospheric pressure chemical ionization (LD-APCI), laser desorption-dual electrospray and atmospheric pressure chemical ionization I (LD - ESI-I-APCI), laser-induced acoustic desorption electrospray ionization (LIAD-ESI), and laser-induced acoustic desorption-dielectric barrier discharge ionization (LIAD-DBDI). Chapters 6 and 7 are largely complementary because in the former one, main attention is paid to practical applications of a wide number of... 

LID Laser-induced desorption LSMS Laser source mass spectrometry... 

Beck, R.D. Weis, P. Hirsch, A. Lam-parth, I. Laser Desorption Mass Spectrometry of Fullerene Derivatives Laser-Induced Fragm tation and Coalescence Reactions. J. Phys. Chem. 1994, 98, 9683-9687. 

Figure 7.5. Experimental configuration for the DIOS-MS experiments, (a) Four porous silicon plates are placed on a MALDI plate. Each of the porous silicon plates contains photopattemed spots or grids prepared through illumination of -type silicon with a 300-S tungsten filament through a mask and an 50 reducing lens, (b) Ibe silicon-based laser desorption/ionization process, in which the sample is placed on the porous silicon plate and allowed to dry, followed by laser-induced desorption/ionization mass spectrometry, (c) Cross section of porous silicon, and the surface functionalities after hydrosilylation R represents phenyl or alkyl chains. (Reproduced with permission from Wei, J. Buriak, J. Siuzdak, G. Desorption/ionization mass spectrometry on porous silicon. Nature 1999, 399, 243-246.)...

Charvat, a. Lugovoj, E. Faubel, M. Abel, M. Analytical laser induced liquid beam desorption mass spectrometry of protonated amino acids and their non-covalently bound aggregates. Eur. Phys. J. 2002, 7(3), 573-582. 

DGE a AC AMS APCI API AP-MALDI APPI ASAP BIRD c CAD CE CF CF-FAB Cl CID cw CZE Da DAPCI DART DC DE DESI DIOS DTIMS EC ECD El ELDI EM ESI ETD eV f FAB FAIMS FD FI FT FTICR two-dimensional gel electrophoresis atto, 10 18 alternating current accelerator mass spectrometry atmospheric pressure chemical ionization atmospheric pressure ionization atmospheric pressure matrix-assisted laser desorption/ionization atmospheric pressure photoionization atmospheric-pressure solids analysis probe blackbody infrared radiative dissociation centi, 10-2 collision-activated dissociation capillary electrophoresis continuous flow continuous flow fast atom bombardment chemical ionization collision-induced dissociation continuous wave capillary zone electrophoresis dalton desorption atmospheric pressure chemical ionization direct analysis in real time direct current delayed extraction desorption electrospray ionization desorption/ionization on silicon drift tube ion mobility spectrometry electrochromatography electron capture dissociation electron ionization electrospray-assisted laser desorption/ionization electron multiplier electrospray ionization electron transfer dissociation electron volt femto, 1CT15 fast atom bombardment field asymmetric waveform ion mobility spectrometry field desorption field ionization Fourier transform Fourier transform ion cyclotron resonance... 

The term 1 or h indicates low or high coverage of adsorbed ethene, as inferred from ethene exposures.h TPD, temperature-programmed desorption LITD, laser-induced thermal desorption 1 FT-MS, Fourier-transform mass spectrometry SIMS, secondary-ion mass spectrometry MS, mass spectrometry T-NEXAFS, transient near-edge X-ray absorption fine structure spectroscopy RAIRS, reflection-absorption infrared spectroscopy. d Data for perdeut-erio species.1 Estimated value. 

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