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Linear time-of-flight mass spectrometer

Mass-to-charge ratios are determined by measuring the time that ions take to move through a field-free region between the source and the detector. Indeed, before it leaves the source, an ion with mass m and total charge / = zc is accelerated by a potential Vs. It electric potential energy Eei is converted into kinetic energy / /  [Pg.126]

The velocity of the ion leaving the source is given by rearranging the previous equation as [Pg.126]

After initial acceleration, the ion travels in a straight line at constant velocity to the detector. The time t needed to cover the distance L before reaching the detector is given by [Pg.126]

Principle of an LTOF instrument tuned to analyse positive ions produced by MALDI. After their formation during a laser pulse, ions are subject to the applied electric field. Ions are continuously accelerated and drift in a free-field region. They travel through this region with a velocity that depends on their m/z ratios. Ions are thus dispersed in time. [Pg.127]

This equation shows that m/z can be calculated from a measurement of t2, the terms in parentheses being constant. This equation also shows that, all other factors being equal, the lower the mass of an ion, the faster it will reach the detector. [Pg.127]


Brown, R. S. Lennon, J. J. Mass resolution improvement by incorporation of pulsed ion extraction in a matrix-assisted laser desorption/ionization linear time-of-flight mass spectrometer. Anal. Chem. 1995,67,1998-2003. [Pg.199]

R. S. Brown and J. J. Lennon. Mass Resolution Improvement by Incorporation of Pulsed Ion Extraction in a Matrix-Assisted Laser Desorption/Ionization Linear Time-of-Flight Mass Spectrometer. Anal. Chem., 67(1995) 1998-2003. [Pg.83]

R. M. Whittal, L. M. Russon, S. R. Weinberger, and L. Li. Functional Wave Time-Lag Focusing Matrix-Assisted Laser Desorption/Ionization in a Linear Time-of-Flight Mass Spectrometer Improved Mass Accuracy. Anal Chem., 69(1997) 2147-2153. [Pg.83]

Another type of dynamic mass spectrometer is the time-of-flight (ToF) analyzer. In 1946, Stephens presented his concept of the linear time-of-flight mass spectrometer (ToF-MS) as the simplest mass separation technique at an American Physical Society meeting in Cambridge, MA.49 Cameron and Eggers first published the design and showed mass spectra for linear ToF-MS in... [Pg.20]

Fig. 1. kHz molecular beam ablation setup with a linear time of flight mass spectrometer. [Pg.62]

Further performance improvements in analysing nucleic acids could be achieved by the introduction of 3-hydroxypicolinic add as matrix [8] and the introduction of delayed extraction in a linear time-of-flight mass spectrometer [9]. If, for MALDI Fourier transform mass spectrometry, the molecular weight range in analysing nucleic add fragments could be extended further this type of MALDI MS would become of significant value due to the extraordinary resolution possible [10, 11]. In order to reach the sensitivity level necessary for MALDI-TOF MS analysis an amplification step has to be incorporated into the sample preparation process for... [Pg.37]

Prieto, M.C. Kovtoun, V.V. Cotter, R.J. Miniaturized Linear Time-of-Flight Mass Spectrometer With Pulsed Extraction. J. Mass Spectrom. 2002, 57, 1158-1162. [Pg.211]

Bahr, U., StahlZeng, J., Gleitsmann, E. and Karas, M., Delayed extraction time-of-flightMALDI mass spectrometry of proteins above 25,000 Da. J. Mass Spectrom., 32, 1111-1116 (1997). Brown, R.S. and Lennon, J.J., Mass resolution improvement by incorporation of pulsed ion extraction in a matrix-assisted laser-desorption ionization linear time-of-flight mass-spectrometer. AwaZ. Chem., 67, 1998-2003 (1995). [Pg.551]

Figure 1. Comparison of analytical results obtained on an industrial polymer by gel permeation chromatography (top) and matrix-assisted laser desorption ionization mass spectrometry (linear time-of-flight mass spectrometer [center] and Fourier transform mass spectrometer [bottom]). From the FT/MS data the polymer can be identified as a substituted polyethylene glycol. Figure 1. Comparison of analytical results obtained on an industrial polymer by gel permeation chromatography (top) and matrix-assisted laser desorption ionization mass spectrometry (linear time-of-flight mass spectrometer [center] and Fourier transform mass spectrometer [bottom]). From the FT/MS data the polymer can be identified as a substituted polyethylene glycol.
Figure 3.19 Linear time-of-flight mass spectrometer based on the Wiiey-McLaren design [551. Reprinted with permission from [54], Copyright 1955, American institute of Physics. Figure 3.19 Linear time-of-flight mass spectrometer based on the Wiiey-McLaren design [551. Reprinted with permission from [54], Copyright 1955, American institute of Physics.

See other pages where Linear time-of-flight mass spectrometer is mentioned: [Pg.185]    [Pg.91]    [Pg.126]    [Pg.91]    [Pg.194]    [Pg.500]    [Pg.294]    [Pg.146]    [Pg.146]    [Pg.314]    [Pg.347]    [Pg.130]   


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