Fast atom bombardment mass determination

While the molecular masses of expanded [n]pericyclines 82,83,122 can easily be determined by GC-MS analysis, higher dehydrocyclooligomers fail to vaporize sufficiently [7]. Fast atom bombardment mass spectometry (FAB-MS) had to be applied for the characterization of the acetal-protected expanded pericyclinones 123-126 and 176 [39]. Attempts to determine the molecular masses of the... 

Simms etal. [8] discuss the quantitative determination of cationic surface active agents at the sub-ppb level in sewage sludges using fast atom bombardment mass spectrometry. 

Wolfender, J.-L. et al.. Comparison of liquid chromatography/electrospray, atmospheric pressure chemical ionization, thermospray and continuous-flow fast atom bombardment mass spectrometry for the determination of secondary metabolites in crude plant extracts, J. Mass Spectrom. Rapid Commun. Mass Spectrom., S35, 1995. 

The average DS as determined by these methods provides only the simplest characterization of these derivatives, and further analysis was necessary to characterize the mixture of SBE bands of different levels of substitution. Due to the presence of the anionic sulfonate substituent, it is possible to use capillary electrophoresis (23), to separate the SBE-CD substitution bands and to characterize the fingerprint of the composition (Fig. 10). Anion exchange chromatography (24) was utilized to isolate separate substitution bands (mono- to deca-derivatives) that were subsequently identified by NMR and fast atom bombardment mass spectroscopy (FAB-MS). 

H Oka, Y Ikai, J Hayakawa, K Masuda, KI Harada, M Suzuki. Improvement of chemical analysis of antibiotics. 19. Determination of tetracycline antibiotics in milk by liquid chromatography and thin-layer chromatography fast atom bombardment mass spectrometry. J AOAC Int 77 891-895, 1994. 

Fast atom bombardment mass spectrometry has been utilized for the quantitative determination of ionic species, in glycerol/water solutions, which are produced by chemical and enzymic reactions. It is shown that reaction constants can be determined in this manner and that they can be accurately related to those determined by other methods used in the analysis of aqueous solutions. The reactions studied include proton dissociation constants for organic acids, an enzyme equilibrium constant, and enzyme rate constants using natural substrates. 

Fast atom bombardment mass spectrometry (FABMS) has become an important addition to the ionization techniques available to the analytical chemist in recent years. It has been particularly useful in a number of diverse applications which include molecular weight determinations at high mass, peptide and oligosaccharide sequencing, structural analysis of organic compounds, determination of salts and metal complexes, and the analysis of ionic species in aqueous solutions. This paper will focus on some aspects of the quantitative measurement of ionic species in solution. The reader is referred to a more comprehensive review for more details of some of the examples given here as well as other applications (1). 

A. Dell, H. R. Morris, H. Egge, H. von Nicolai, and G. Strecker, Fast-atom-bombardment mass spectrometry for carbohydrate structure determination, Carbohydr. Res., 115 (1983) 41-52. 

HPLC with column switching and mass spectrometry was applied to the online determination and resolution of the enantiomers of donepezil HC1 in plasma [38]. This system employs two avidin columns and fast atom bombardment-mass spectrometry (FAB-MS). A plasma sample was injected directly into an avidin trapping column (10 mm x 4.0 mm i.d.). The plasma protein was washed out from the trapping column immediately while donepezil HC1 was retained. After the column-switching procedure, donepezil HC1 was separated enantioselectivity in an avidin analytical column. The separated donepezil HC1 enantiomers were specifically detected by FAB-MS without interference from metabolites of donepezil HC1 and plasma constituents. The limit of quantification for each enantiomer of donepezil HC1 in plasma was 1.0 ng/ml and the intra-and inter-assay RSDs for the method were less than 5.2%. The assay was validated for enantioselective pharmacokinetic studies in the dog. 

M. Sawada et al., Chiral recognition in host-guest complexation determined by the enantiomer-labeled guest method using fast atom bombardment mass spectrometry. J. Am. Chem. Soc. 117, 7726-7736 (1995)... 

H.J. Yang, Y.-Z. Chen, Stereochemical effects in mass spectrometry. XIII-Determination of absolute configuration by fast atom bombardment mass spectrometry. Org. Mass Spectrom. 27, 736-740 (1992)... 

M. Katagi, M. Tatsuno, M. Nishikawa and H. Tsuchihashi, On-line solid-phase extraction liquid chromatography-continuous flow frit fast atom bombardment mass spectrometric and tandem mass spectrometric determination of hydrolysis products of nerve agents alkyl methylphosphonic acids by p-bromophenacyl derivatization, J. Chromatogr., A, 833, 169-179 (1999). 

Recently, the enantiomeric excess of a-amino acid ester hydrochlorides has been determined directly by using FAB (fast atom bombardment) mass spectrometry without chromatographic separation of the enantiomers. ... 

S. Murao, K.Tanaka, and I. Nojima, Primary structure of paim I, an alpha-amylase inhibitor from Streptomyces corchorushii, determined by the combination of Edman degradation and fast atom bombardment mass spectrometry, Biochemistry 26 (1987), 6483-6488. 

J. Gonzalez, T. Takao, H. Hori, V. Besada, R. Rodrignez, G. Padron, and Y. Shimonishi, A method for determination of N-glycosylation sites in glycoproteins by collision-indnced dissociation analysis in fast atom bombardment mass spectrometry Identification of the positions of carbohydrate-linked asparagine in recombinant a-amylase by treatment with peptide-A-glycosidase F in 0-labeled water, A flZ. Biochem. 205 (1992), 151-158. 

The molecular masses of the complex compounds are conveniently determined by soft-ionization methods, such as fast atom bombardment mass spectrometry (FAB-MS), in the positive and/or negative mode. This method can easily be applied to the ionization of non-volatile, non-derivatized, polar compounds, and is particularly suited to the analysis of saponins. Extremely valuable is the use of high resolution FAB-MS (HRFAB-MS), which provides the exact mass of high molecular weight compounds, and consequently their molecular formulae. 

A study of the fast atom bombardment mass spectra and low-energy collision activation tandem mass spectra of a series of monoquatemary and bisquatemary bisbenzylisoquinoline Thalictrum alkaloids was undertaken [143]. It was determined that the relative molecular mass of the free base alkaloid and its bisquatemary salt can be obtained from FAB data, but that the monoquatemary ammonium salt derivatives produce only a (M-X)+ ion, thus precluding the determination of the relative molecular mass. For example, the bisquatemary iodide ammonium salts produced ions (M-I)+, (M-I-HI)+, and (M-I-CH3I)+. The relative molecular mass of the counter anion may be determined with facility, thereby affording the relative molecular mass of the alkaloid. However, with a monoquatemary ammonium salt such as a monochloride, only a (M-X)+ ion is produced, and there is insufficient mass spectral data to determine its counter anion from positive-ion FAB. Negative-ion FAB was unable to be employed to determine absolutely the counter anion of the alkaloid, since chloride anions occur as common background anions. 

Because of the complexity of the polyether antibiotics little progress has been made in structure determination by the chemical degradation route. X-ray methods were the techniques most successfully applied for the early structure elucidations. Monensin, X206, lasalocid, lysocellin, and salinomycin were included in nineteen distinct polyether x-ray analyses reported in 1983 (190). Use of mass spectrometry (191), and 1H (192) and 13C nmr (141) are also reviewed. More recently, innovative developments in these latter techniques have resulted in increased applications for structure determinations. For example, heteronuclear multiple bond connectivity (hmbc) and homonudear Hartmann-Hahn spectroscopy were used to solve the structure of portimicin (14) (193). Fast atom bombardment mass spectrometry was used in solving the structures of maduramicin alpha and co-factors (58). 

A fraction of the shocked hexane recovered from the container was directly injected into TCD-GC and FID-GC to determine dissolved H2 and low-molecular-weight hydrocarbons (LHCs), respectively. Another fraction of the shocked hexane was subsequently charged with an internal standard and concentrated by a rotary evaporator. High molecular-weight hydrocarbons (HHCs) in the concentrated solution were analyzed by FID-GC and GCMS. Soot-like materials were analyzed by a fast atom bombardment mass spectrometer (FABMS). 

The particular use of mass spectrometry techniques was of fundamental relevance in the structural determinations of CMHs from different species, including analytical variations as fast atom bombardment mass spectrometry (FAB/MS), electronspray ionization (ESI-MS) and low energy collision-induced dissociation tandem mass spectrometry (ESI-... 

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