Fourier Transform Ion Cyclotron Resonance Mass Spectrometry FTICR

The gas-phase basicity (GB) of 3-thio-5-oxo 1, 5-thio-3-oxo 2, and 3,5-dithio 4 derivatives of 2,7-dimethyl-[l,2,4]-triazepine (Figure 1) has been measured by means of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry and complemented with theoretical calculations. The experimental FTICR results are discussed in Section 13.14.4.1.l(i). The structures and vibrational frequencies of all stable protonated tautomers and all transition states connecting them have been obtained by means of the B3LPY density functional method, together with 6-31G basis set expansion. The final energies were obtained at the B3LYP/6-311 + G(3df,-2p) level (2002JPC7383). 

Reemtsma,T.,These, A., Springer, A., and Linscheid, M. (2008). Differences in the molecular composition of fulvic acid size fractions detected by size-exclusion chromatography—On fine Fourier transform ion cyclotron resonance (FTICR-) mass spectrometry. Water Res. 42, 63-72. 

The coordination of transition metals is known to influence the keto-enol tautomerism in the condensed phase" . The effect of coordination of bare Fe+ ions on the keto-enol equilibrium of phenol was investigated by means of generation of various cyclic [Fe,Cg, He, 0]+-isomers. These isomers were characterized by collisional activation (CA) and Fourier transform ion cyclotron resonance (FTICR) mass spectrometry" . It was shown that the energy difference between the phenol-iron complex 65 and the keto isomer 66 is not perturbed by the presence of the iron cation in comparison with the uncom-plexed isomers 3 and 4 (equation 25). Thus, the energy difference for both the neutral and the Fe+-coordinated systems amounts to ca 30 kJ moC in favor of the phenolic tautomer. 

In this chapter, two examples of gas-phase oxidations using O2 are discussed in order to illustrate the performance as well as the limitations of gas-phase studies. While some of the experimaital data have been reported previously, the key experiments in this work were conducted by using Fourier-transform ion-cyclotron resonance (FTICR) mass spectrometry [42] ). 

To this end, we have studied the gas phase reactions of ethylene complexes M(C2H4)+ of the 1st row transition metal cations (M = Sc - Zn) with molecular oxygen by means of Fourier Transform Ion Cyclotron Resonance (FTICR) Mass Spectrometry. This model reaction migth serve as a test for the capability of the individual metal cations with respect to oxygen and C-H-activation as well. For comparison the reactions of the radical cation C2H4+ with oxygen as well as those of M(C2H4)+ with M = H, Na, and Mg have also been included in this comprehensive gas phase study. 

Figure 2.19. Schematic of a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer (a) and a cylindrical cell (b). Reprinted from A. Westman-Brinkmalm and G. Brinkmalm (2002). In Mass Spectrometry and Hyphenated Techniques in Neuropeptide Research, J. Silberring and R. Ekman (eds.) New York John Wiley Sons, 47-105. With...

The same group studied the lithium cation basicities of a series of compounds of the general formula R R R PO, i.e. phosphine oxides, phosphinates, phosphonates and phosphates, by using Fourier Transform Ion Cyclotron Resonance (FTTCR) mass spectrometry. A summary of their results is shown in Figure 4. The effect of methyl substitution on LCA as well as the correlation between LCA and PA was also investigated by Taft, Yanez and coworkers on a series of methyldiazoles with an FTICR mass spectrometer. They showed that methyl substituent effects on Li binding energies are practically additive. 

Ion-molecular reactions are used to resolve isobaric interferences, as discussed, in ICP-MS with a collision/reaction cell or by utilizing ion traps. The mass spectra of Sr, Y and Zr (Fig. 6.10a) without O2 admitted into the collision cell and (Fig. 6.10b) with 10 Pa Oj are different. By introducing oxygen, selective formation of YO and ZrO, but not SrO, is observed. This behaviour of different oxide formation is relevant for an interference free determination of Sr. Ultrahigh mass resolving power ICP mass spectrometry (at m/Am 260 000) selectively removes unwanted ions prior to transfer to the FTICR analyzer cell by gas-phase chemical reactions, e.g., for separation of Ca from " Ar+ obtained with a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer equipped with a 3 tesla superconducting magnet. ... 

Alkali metal ion/molecule association reactions have been exploited in various mass spectrometric methods since the early 1970s. Initial studies were to determine metal ion affinities of simple compounds, with use of Fourier transform ion cyclotron resonance (FTICR) mass spectrometers. Alkali ions offer unique and interesting potential in analytical chemistry and studies of chemical dynamics. Consequently, the use of metal ions as reagents for Cl mass spectrometry has been developed. The major advances in the apphcation of MS as a routine analytical instmment using the complex ion/molecule chemistry came arotmd in the past decades. They include atmospheric pressure chemical ionization (APCI), proton transfer reaction mass spectrometry (PTR-MS), selected ion flow tube mass spectrometry (SIFT-MS), ion attachment mass spectrometry (lAMS) and ion molecrtle reaction mass spectrometry (IMM-MS). 

Resolution does not affect the accuracy of the individual accurate mass measurements when no separation problem exists. When performing accurate mass measurements on a given component in a mixture, it may be necessary to raise the resolution of the mass spectrometer wherever possible. Atomic composition mass spectrometry (AC-MS) is a powerful technique for chemical structure identification or confirmation, which requires double-focusing magnetic, Fourier-transform ion-cyclotron resonance (FTICR) or else ToF-MS spectrometers, and use of a suitable reference material. The most common reference materials for accurate mass measurements are perfluorokerosene (PFK), perfluorotetrabutylamine (PFTBA) and decafluorotriph-enylphosphine (DFTPP). One of the difficulties of high-mass MS is the lack of suitable calibration standards. Reference inlets to the ion source facilitate exact mass measurement. When appropriately calibrated, ToF mass... 

Currently PCR and mass spectrometry are performed by two separate instruments. However, there is no reason why PCR followed by simple automated cleanup and mass spectrometry cannot be incorporated into a single integrated instrument. Essentially every configuration of the modern ESI mass spectrometer has been used successfully for the analysis of PCR products, from the highest to the lowest resolution involving. Fourier transform ion cyclotron resonance (FTICR), triple quadrupole, quadrupole-time of flight (Q-TOF), and ion trap.22-24 MS discriminates between two structurally related PCR products by MW difference. Mass accuracy is needed to differentiate the... 

Many heterocycles, for instance NH-azoles, have acid-base properties of either or both proton gain (basicity) and proton loss (acidity) [85], The possibility of studying such processes in the gas-phase (mass spectrometry and Fourier transform ion cyclotron resonance - FTICR - spectroscopy) provides theoreticians with values... 

The technique of laser desorption (LD) has been widely used in mass spectrometry (J, 2) to desorb and to ionize high molecular weight or other nonvolatile samples, most often using time-of-flight (3. 4 ) or Fourier transform ion cyclotron resonance (FTICR) ( 5. 6 ) mass spectrometers for mass analysis. In this technique, highly focussed laser irradiation, most often with a power density of at least 10° W/cm, is used to desorb and ionize a solid sample that has been inserted into the high vacuum system of the mass spectrometer. 

In addition to H and NMR analysis, TLC coupled in an offline manner with electrospray mass spectrometry (ESI-MS) and high-resolution ESI Fourier transform ion cyclotron resonance (FTICR) MS for isolation and characterization of two novel lupane triterpenoids from Paullinia pinnata L. 6P-(3 -methoxy-4 -hydroxybenzoyl)-lup-20(29)-ene-one and 6P-(3 -methoxy-4 -hydroxybenzoyl)-lup-20(29)-ene-ol, which are suspected to play a crucial role in the plant s wound healing effects [32]. The extract from Paullinia pinnata L. was subjected to an exhaustive isolation procedure starting with two consecutive column chromatography purifications on silica gel different ratios of chloroform-methanol were used as eluent. The triterpenoid-containing fraction was purified on preparative silica gel TLC plate with chloroform-methanol (9 1, v/v) as a developing solvent. The two resulting lupane bands were finally submitted to MS analyses. 

Relative mass is an intrinsic molecular property which, when measured with high accuracy, becomes a unique and unusually effective parameter for characterization of synthetic or natural biomolecules. Mass spectrometry based methods can be broadly applied not only to unmodified synthetic biomolecules, but also to modified synthetic and natural biomolecules (e.g. glycosylated proteins). The level of mass accuracy one obtains during the measurement will depend on the capabilities of the mass analyser used. Quad-rupole and TOE instruments yield lower mass accuracies than sector or Fourier transform ion cyclotron resonance (FTICR) instruments. High mass accuracy is not only necessary for qualitative analysis of biomolecules present in a sample, but is necessary to provide unambiguous peak identification in a mass spectrum. 

FTICR. Fourier-transform ion cyclotron resonance GC/IRMS. gas chromatography isotope ratio mass spectrometry... 

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... 

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]. 

The development of mass spectrometric techniques, such as fast atom bombardment mass spectrometry (FAB-MS), ° ° Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), ° and tandem mass spectrometry (MS"), ° allowed enantiodiscrimination of chiral ion-dipole complexes the gas phase. These techniques and others will be illustrated in detail in the next Section 3. 

In the present review, a new variation on an existing experimental method will be used to show how accurate unimolecular dissociation rate constants can be derived for thermal systems. For example, thermal bimolecular reactions are amenable to study by use of several, now well-known, techniques such as (Fourier transform) ion cyclotron resonance spectrometry (FTICR), flowing afterglow (FA), and high-pressure mass spectrometry (HPMS). In systems where a bimolecular reaction leads to products other than a simple association adduct, the bimolecular reaction can always be thought of as containing a unimolecular... 

In 1974, Comarisov and Marshall60 developed Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). This technique allows mass spectrometric measurements at ultrahigh mass resolution (R = 100000-1000000), which is higher than that of any other type of mass spectrometer and has the highest mass accuracy at attomole detection limits. FTICR-MS is applied today together with soft ionization techniques, such as nano ESI (electrospray ionization) or MALDI (matrix assisted laser/desorption ionization) sources. 

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