Analytical Fourier transform mass

R. B. Cody, J. A. Kinsinger, Sahba Ghaderi, I. J. Amster, F. W. McLafferty, and C. E. Brown, "Developments in Analytical Fourier Transform Mass Spectrometry," Analytics Chimica Acta, 178. 43-66 (1985). 

Instrumentation and Application Examples in Analytical Fourier Transform Mass Spectrometry... 

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... 

Laser desorption methods (such as LD-ITMS) are indicated as cost-saving real-time techniques for the near future. In a single laser shot, the LDI technique coupled with Fourier-transform mass spectrometry (FTMS) can provide detailed chemical information on the polymeric molecular structure, and is a tool for direct determination of additives and contaminants in polymers. This offers new analytical capabilities to solve problems in research, development, engineering, production, technical support, competitor product analysis, and defect analysis. Laser desorption techniques are limited to surface analysis and do not allow quantitation, but exhibit superior analyte selectivity. 

Fourier transform mass spectrometry (FTMS) is a rapidly growing technique of increasing analytical importance. Foremost among its many attributes are its high mass resolution and wide mass range capabilities, as well as its ability to store ions. This relatively new technique has been employed in a wide variety of applications, ranging from the exact mass measurement of stable nuclides to the determination of peptide sequences. The future holds considerable promise both for the expanded use of FTMS in a diverse range of chemical problems, as well as advances in the capabilities of the technique itself. 

All experiments were performed using a Nicolet Analytical Instruments FTMS-2000 dual-cell Fourier transform mass spectrometer with optional GC and laser desorption interfaces. The FTMS-2000 dual cell is specially constructed of stainless steel with low magnetic susceptibility. This permits very efficient ion transfer between the source and analyzer cells, if the cells are properly aligned in the magnetic field. 

Analytical Applications of Laser Desorption—Fourier Transform Mass Spectrometry for Nonvolatile Molecules... 

FT-ICR, first developed more than a decade ago (Comisarow and Marshall, 1974a,b), has become very popular in recent years for both analytical and ion/molecule reaction studies. In the literature this method is also frequently termed Fourier transform mass spectrometry (FTMS). The term FT-ICR, however, indicates the physical principles of the method more precisely and is less confusing the mathematical operation of Fourier transformation can also be applied to some other forms of mass spectrometry such as time-of-flight mass spectrometry as has been demonstrated recently (Knorr et al., 1986). 

Trends in Analyt. Chem. 13, Special Issue Fourier Transform Mass Spectrometry (C. L. Wilkins, ed.), 1994, p. 223-251. 

Mass spectrometry has become more useful In the support of electronic development and manufacturing processes. Fourier transform mass spectrometry, the latest advance in this analytical method, Is another step forward in versatility, sensitivity and reproducibility in analytical characterization, qualification and quantification of raw materials and contaminants as used in electronic devices. A review will be provided of basic instrument hardware and interfacing, significant operating parameters and limitations, and special inlet systems. Emphasis will be placed on material evaluation, process control and failure analysis. Data handling will be reviewed using appropriate examples encountered in material and failure analysis. 

These developments [together with the availability of high-performance instruments, e.g., Fourier transform-mass spectrometry (FT-MS) and Orbitrap] make possible the application of MS in many different fields. The problem is to individualize the best instrumental choices and the related parameterization to obtain the analytically more valid results, which allows to propose new, highly specific analytical methods. 

It is clear that laser desorption Fourier transform mass spectrometry has significant potential as a polymer analysis tool. It works especially well for polar polymers and additives witii molecular weights lower than 10000 Da. AAftth proper attention to analytical details, it is a highly accurate and quite specific way to characterize tiiese substances and can provide unrivaled mass resolution. As is obvious from this chapter, the application of LD-FTMS to polymer analytical problems is an active area of investigation in many laboratories. AAftth the continuing proliferation of commercial FTMS instruments, LD-FTMS applications of polymer analysis should be expected to expand for the foreseeable future. There is no question tiiat tiiis method provides a versatile alternative to tire numerous less specific analytical methods employed to date. 

Castoro, J. A., and Wilkins, C. L., High Resolution Matrix-Assisted Laser Desorption/Ionization of Small Proteins by Fourier Transform Mass Spectrometry, Analytical Chemistry, 65, 2621, 1993. 

FTMS Fourier transform mass spectrometer (analytical device)... 

Fourier transform mass spectrometry (ftms) is an ion cyclotron resonance method (3,4). This method is currently limited to masses less than 20,000. Thus, it works well for lower molecular mass polymers. Often it is used with MALDI. However, the MALDI process is so energetic that the initial velocity of the analytes can cause some intensity difficulties that make the method difficult to quantify. Because of the expense of the magnet required to obtain quahty data with this method, only a few laboratories use this method. 

Charles 1. Wilkins is currently a Distinguished Professor in the Department of Chemistry and Biochemistry at the University of Arkansas (Fayetteville). His interests inclnde mass spectrometry of polymer and copolymer materials, Fourier transform mass spectrometry, and the development of new methods to improve the utility of analytical mass spectrometry. Past research has dealt with applications of laboratory computers in chemistry, graph theoretic analysis of chemical problems, and research in chemometrics. Investigations of hyphenated analytical systems such as gas chromatography-infrared mass spectrometry and HPLC-NMR have also been of interest. He is the author of more than 235 scientific papers and 21 book chapters, in addition to editing eight books on a variety of chemistry topics. 

McCrery, D. a., E. B. Ledford, Jr., and M. L. Gross Laser Desorption Fourier Transform Mass Spectrometry. Analyt. Chemistry 54, 1435 (1982). 

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 2 Bronsted acid Cl mass spectra of H-Val-Pro-Leu-OH using (A) NH4+, (B) CjHs+and (C) NjOH as reagent ions. Reprinted with permission from Speir JP, Gorman GS, Cornett DS and Amster IJ (1991) Controlling the dissociation of peptide ions using laser desorption/chemical ionization Fourier transform mass spectrometry. Analytical Chemistry 6Z 65-69. Copyright (1991) American Chemical Society.

Fourier transform mass spectrometry (FTMS) offers the highest mass resolution and mass measurement accuracy of all mass analyzers. FTMS, also referred to as Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS), can be adapted to a wide variety of ion sources and ion dissociation methods.The fundamental behavior of ions in FTMS instmments is based on the principle of ion cyclotron resonance (ICR), conceived and developed by E. O. Lawrence in the 1930s to build ion accelerators for nuclear physics experiments. ICR was first implemented in mass spectrometry in an instrument called the omegatron, developed by scientists at the National Bureau of Standards in the 1950s. Advances such as the application of Fourier transform methods to ICR spectrometry and the trapped analyzer cell resulted in the development of a powerful analytical instmment. 

Yao, j. Scott, J. R. Young, M. K. Wilkins, C. L. Importance of matrix analyte ratio for buffer tolerance using 2,5-dihydroxybenzoic acid as a matrix in matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry and matrix-assisted laser desorption/ionization-Time of flight. J. Am. Soc. Mass Spectrom. 1998, 9, 805-813. 

Identification of stmctures of toxic chemicals in environmental samples requires to use modern analytical methods, such as gas chromatography (GC) with element selective detectors (NPD, FPD, AED), capillary electrophoresis (CE) for screening purposes, gas chromatography/mass-spectrometry (GC/MS), gas chromatography / Fourier transform infra red spectrometry (GC/FTIR), nucleai magnetic resonance (NMR), etc. 

B. Asamoto (ed.), FT-ICR/MS Analytical Applications of Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, VCH Publishers, New York, NY (1991). 

Different experimental approaches were applied in the past [6, 45] and in recent years [23, 46] to study the nature of the organic residue. But the results or their interpretation have been contradictory. Even at present, the application of modem analytical techniques and optimized electrochemical instruments have led to different results and all three particles given above, namely HCO, COH and CO, have been recently discussed as possible methanol intermediates [14,15,23,46,47]. We shall present here the results of recent investigations on the electrochemical oxidation of methanol by application of electrochemical thermal desorption mass spectroscopy (ECTDMS) on-line mass spectroscopy, and Fourier Transform IR-reflection-absorption spectroscopy (SNIFTIRS). 

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