FT-ICR mass spectra

Fig. 5.6 APPI FT-ICR mass spectra from the samples with different hydrogenation degree. Top panel for 3.8 wt% sample and bottom panel 5.0 wt% of hydrogen according to chemical analysis...

Figure 1. FT-ICR mass spectra of black mirrorlike sublimed fullerene film showing presence of (La C,) fullerenes. For the top panel the pulsed decelerator responsible for slowing the clusters down to be trapped in the analysis celt was optimized for the CM-C70 mass region. For the bottom panel it was optimized for the region around C. ...

Figure 4. FT-ICR mass spectra showing evidence for the production of boron and boron/potassium doped 60-ati n fuiloenes. The bottom panel shows the result of reaction with ammonia. Note that the boron-doped clusters have been titrated with ammonia, demonstrating that the boron is substituting for a carbon as part of the fullerene cage. Note also that the clusters in the top panel marked K(K C4o) and K2(K C o) are missing after reaction with ammonia in the bottom panel, demonstrating that the extra potassium atoms were on the outside, unprotected by the fullerene cage.

T Solouki, L Pas-a-Tolis, GS Jackson, S Guan, AG Marshall. High resolution multistage MS, MS2 and MS3 matrix-assisted laser desorption/ionization FT-ICR mass spectra of peptides from a single laser shot. Anal Chem 68(21) 3718-3725, 1996. 

Stenson, A.C., Marshall, A.C. and Cooper, W.T. (2003) Exact masses and chemical formulas of individual Suwannee River fulvic acids from ultrahigh resolution ESI FT-ICR mass spectra. Analytical Chemistry 75, 1275-1284. 

Fig. 10.12 ESI-FT-ICR mass spectra of (a) the fluoroacetic acid, pH 3. The inserts show native intact hem-protein complex of horse isotopic resolutions for the 9- and 1 7-fold heart myoglobin (b) spectrum ofthe denatured protonated molecular ions [145]. apoprotein upon dissociation of hem in tri-...

Laser desorption FT-ICR mass spectra MB82, and MB91. 

Figure 6. Ultrahigh resolution FT-ICR mass spectra. Each transient was acquired for 1.02 sec and had 250 msec relaxation time. The 867 peak in (e) is the carbon-13 satellite of the 866 peak, (f) is a plot of the mass resolution versus ion mass for the spectra of (a)-(e).

Figure 7. FT-ICR mass spectra of cyclopentadienyl chromium dicar-bonylthionitrosyl as a function of reaction time. The chemistry derived from this data is discussed in the text.

Figure 2.4. (a) Positive-ion time-resolved FD FT-ICR mass spectra of mid-boiling crude oil distillate that was acquired at lowmedium, and high emitter current settings (b) Mass scale-expanded spectrum shows compositionally resolved ions. (Reproduced from ref. 14 by permission of the American Chemical Society, Washington, DC, copyright 2003.)... 

Figure 1 Comparison of parts of the SORI-CAD ESI FT-ICR mass spectra of the [M + 3 H] + precursor ions of (A) nisin A (wild-type nisin), (B) nisin S5A, (C) nisin H27 K, and (D) nisin I30W-H, showing the region containing doubly charged fragment ions. The ions in the transgenic variants that are shifted in mass compared to nisin A are marked with asterisks. (Reprinted from Lavanant H, Heck A, Derrick PJ, et al. (1998) Characterization of genetically modified nisin molecules by Fourier transform ion cyclotron resonance mass spectrometry. European IVIass Spectrometry 4-. 405-416, with permission IM Publications.)...

Figure 1.22 LD/EI/FT/ICR mass spectra of ULTRANOX 626 diphosphite in various solid polymers (a) 0.1% in PP (b) 0.25% in acrylonitrile-butadiene-styrene (c) 10% in PET. Direct analysis of polymeric film or extraction was necessary to produce these spectra. Reproduced from Xiang and co-workers, American Chemical Society [72]...

LD/EI/FT/ICR mass spectra of the same additive present at higher concentrations in PET and ABS polymers are shown in Figure 1.22b and c. This time, there does not appear to be significant oxidation of the additive, since no signals from the phosphate or diphosphate oxidation products are observed. 

Fig. 50. FT-ICR mass spectra of hot-toluene extract of fullerene material produced by laser evaporization of a 10% LajOj/graph-ite composite rod. This was exposed to air and moisture. Reproduced from Chai et al. (1991).

Improving the mass resolution (definition is covered in Section 5.1.1.1.1) reduces this m/q spread, thereby allowing for the separation of secondary ion signals of similar (nominal) m/q ratios. Minimal spread is noted in the FT-ICR mass spectra shown in Figure 5.2(c) where an extremely High Mass Resolution (HMR) was used (Smith et al. 2013). 

Although under high laser power density ( 10 W/cm ), the laser desorption process may alter the sample and create fiillerene species, careful adjustment of the laser power and experimental parameters can eliminate fiillerene production 20). At 2x10 W/cm we did not observe any laser produced fiillerene from graphite, and LD FT-ICR mass spectra of pure C6o and C o samples at this laser power contained only Ceo and C70 ions, respectively. 

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