Fourier transform mass spectrometry-negative

Laser ablation coupled to ion cyclotron resonance Fourier transform mass spectrometry (in both positive and negative ion modes) can be used to distinguish natural and... 

Fourier Transform Mass Spectrometry Studies of Negative Ion Processes... 

Aminoanthracene, 1- and 2-, reactions, effects of ion source temperature, 185,187/ Analytical Fourier transform mass spectrometry, instrumentation and application examples, 81-98 Apodization, 27,28 Applications, future, 14,15 Aromatic amines, negative ion chemical ionization, 176... 

Munson and Field reported in 1966 on a technique of ionizing molecules by gas phase ion-molecule reactions, which they called chemical ionization (Cl). In this way, break-up of the molecules can be greatly reduced or even avoided. Thus, measured ion currents can be correlated with the densities of the respective parent neutral compounds, allowing for on-line monitoring of rather complex gas mixtures. The fundamental principles of gas phase ion chemistry on which Cl is based, as well as the instrumentation for Cl, have been reviewed in great detail by Harrison." The wide variety of Cl methods that has been developed includes Medium Pressure Mass Spectrometry, Fourier Transform Mass Spectrometry, Quadrupole Ion Trap Mass Spectrometry, Pulsed Positive Ion-Negative Ion Chemical Ionization, and Atmospheric Pressure Ionization Mass Spectrometry (API-MS). Of these, API-MS has developed into a very reliable and widely used technique for analysis of VOCs in flavor release studies and human breath. A variety of API-MS applications in these fields of research has been described in a recent volume by Roberts and Taylor. ... 

Results of Fourier-transform mass spectrometry (FT-MS) studies with the carbon oxides 3-5 conclusively demonstrate that one reaction pathway to the formation of fullerenes is the coalescence of large cyclocarbon ions [21, 23], In the negative-ion mass spectra of the carbon oxides, the expected successive losses of CO molecules from the precursor anions to give the cyclocarbon ions Cii, and were observed. In the positive-ion mode, gas-phase coalescence reactions of the cyclocarbon ions produced fullerene ions. Ion-molecule reactions starting from the cyclocarbon cations Cl s (formed by laser desorption of 3), and 2 (formed from 4) led through distinct intermediates Cjg -... 

MS, Mass spectrometry El, electron impact Cl, chemical ionization MID, multiple ion detection PICI, positive-ion chemical ionization NICI, negative-ion chemical ionization SIM, selected ion nmonitoring TSP, thermospray PPINICI, pulsed positive ion-negative ion chemical ionization ECD, electron-capture detector NPD, nitrogen/phosphorous detector NSTD, nitrogen-selective thermionic detector FT-IR, Fourier transform infrared spectrometry. 

Octadecyl sulfate sodium salt (Ci8H37-0-S03 Na+) was examined by laser desorption (LD) Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) in the negative mode resulting in [M - H] ions. Little fragmentation was observed under these conditions [28]. 

E. Vukelic, A. D. Zamfir, L. Bindila, M. Froesch, J. Peter-Katalinic, S. Usuki, and R. K. Yu, Screening and sequencing of complex sialylated and sulfated glycosphingolipid mixtures by negative ion electrospray Fourier transform ion cyclotron resonance mass spectrometry, J. Am. Soc. Mass Spectrom., 16 (2005) 571—580. 

The negative ion mass spectra of 21 was studied by an electron im-pact/Fourier transform ion cyclotron resonance mass spectrometry method (95MI13). 

The presence of pentosyUiexosides, trisaccharides and tetrasaccharides has been reported in different wines using positive- and negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (Cooper and Marshall 2001). Nevertheless, at present there are still a number of minor carbohydrates in wines without a conclusive identification. 

Muddiman DC, Null AP, and Hannis JC (1999) Precise mass measurement of a double stranded 500 base-pair (309 kDa) polymerase chain reaction product by negative ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Rapid Communications in Mass Spectrometry 13 1201-1204. 

A wide variety of other MS techniques are used to detect explosives. Two notable techniques are Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and CE-MS. FT-ICR-MS is used to probe pseudomolecular ion formation of RDX, PETN, and TNT using several ionization sources including EDI, El, electron capture ionization (EC), and chemical ionization (Cl). Analyses are performed both in the positive and negative ionization mode, and identities are assigned to the major pseudomolecular ion peaks seen in the spectra from each explosive [198]. TTie composition of several explosive compounds from postblast residue is assessed with FT-ICR-MS by identifying the explosive and inactive ingredients in a smokeless powder, TNT,... 

Qian, K., Robbins, W.K., Hughey, C.A., Cooper, H.J., Rodgers, R.P, Marshall, A.G. (2001) Resolution and identification of elemental compositions for more than 3000 crude acids in heavy petroleum by negative-ion microelectrospray high-field Fourier transform ion cyclotron resonance mass spectrometry. Energy Fuels, 15,1505-1511. 

Stanford, L.A. Rodgers, R.P. Marshall, A.G. Czamecki, J. Wu, X.A. Compositional Characterization of Bitu-mcn/Watcr Emulsion Films by Negative-and Positive-Ion Electrospray Ionization and Field Desorption/Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry. Energy Fuels 2007,21,963-972. 

Gorshkov, M. V. Guan, S. Marshall, A. G. Dynamic ion trapping for Fourier-transform ion cyclotron resonance mass spectrometry Simultaneous positive-and negative-ion detection. Rapid Commun. Mass Spectrom. 1992, 6, 166. 

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