Fast atom bombardment-mass spectrometry samples

E. Davoli, R. Fanelli and R. Bagnati, Purification and analysis of dmg residues in urine samples by on-line immunoaffinity cliromatography/bigh-performance liquid cliro-matography/continuos-flow fast atom bombardment mass spectrometry . Anal. Chem. 65 2679-2685 (1993). 

In line with the policy of Advances to provide periodic coverage of major developments in physical methodology for the study of carbohydrates, A. Dell (London) here surveys the use of fast-atom-bombardment mass spectrometry in application to carbohydrates. This technique has achieved rapid prominence as the soft ionization technique of choice for structural investigation of complex carbohydrate sequences in biological samples. The author s extensive personal involvement in this field makes her chapter a critical, state-of-the-art overview for the specialist, as well as a valuable primer for the reader unfamiliar with this technique. 

Other MS based analytical approaches have occasionally been applied to ancient resin samples, in particular for paint varnishes. Such techniques include FABS (fast atom bombardment mass spectrometry) [35], MALDI (matrix assisted laser desorption-ionization mass spectrometry) and GALDI (graphite assisted laser desorption-ionization mass spectrometry) [36 38]. 

R. M. Caprioli, T. Fan, and J. S. Cottrell. Continuous-Flow Sample Probe for Fast Atom Bombardment Mass Spectrometry. Anal. Chem., 58(1986) 2949-2954. 

Caprioli, R. M. Fan, T. Cottrell, J. S. A continuous-flow sample probe for fast atom bombardment mass spectrometry. Anal. Chem. 1986, 58, 2949-2954. 

The low-resolution mass spectrum of Indinavir sulfate was measured using fast atom bombardment mass spectrometry on a JEOL HXl lOA mass spectrometer set at a resolution of 5000. The sample was ionized from a 5 1 dithiothreitol dithioerythritol matrix using xenon as the FAB gas. The low-resolution mass spectrum [12] ofindinavir is shown in Figure 14, while the structures of the structurally significant fragment ions are illustrated in Figure 15. 

Fast-atom bombardment mass spectrometry (FAB-MS) has been applied to the identification of diterpenoid compounds and their oxidation products. Similarly, laser-induced desorption mass spectrometric (LDMS) techniques have been applied to the identification of natural and synthetic organic pigments in microscopic paint samples prepared as cross sections [60]. 

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. 

In order to assign the disulfide bonds of these molecules fast atom bombardment mass spectrometry (FABMS) which has been used not only to confirm amino acid sequence data but also to elucidate post-translational modifications of proteins, such as disulfide bonds, has been employed. For this purpose a sample of native Er-2, containing four methionines, was subjected to CNBr cleavage and without further fractionation directly... 

General (PAF and lysoPAF). The basic objective here is to examine the spectrum of a PAF sample subjected to fast atom bombardment-mass spectrometry (FAB-MS). The predominant feature of the resulting spectrum is the formation of a protonated mass ion. In actual fact, there is some cleavage of the molecule, but it is not extensive. These ions can, however, be used for diagnostic purposes. 

Prabhakar et al. [56] developed and validated six HPLC assay methods which permitted resolution of tailing problems for the separation of phenothiazine bioactive components and preservatives in liquid pharmaceutical formulations by using cyano-, C-8, C-18, and cation-exchange phases. The mass spectrometry (MS) of phenothiazines in biological samples is important in forensic analysis. However, since most phenothiazines having long piper-azinyl side chains are thermolabile, the phenothiazines are not suitable for conventional gas chromatography (GC)/MS analysis. Therefore, a system of capillary HPLC/fast atom bombardment-mass spectrometry (FAB-MS) was... 

Isolation of Metabolites from Poultry Bile for Spectral Identification. Pooled samples of bile from poultry receiving feed medicated at 25 ppm semduramicin sodium for 7 days were extracted with ethyl acetate followed by chloroform. Abundant metabolites were isolated by collection of fractions from repeated injections on a normal phase silica HPLC column. The recovered fractions were analyzed by Fast Atom Bombardment Mass Spectrometry and proton NMR spectroscopy. 

In fast-atom bombardment mass spectrometry (FAB) primary neutral atoms of energies 3—10 keV are used to sputter clusters and molecular ions from the sample. 

Lehmann, W.D., Kessler, M., and Konig, W.A., Investigations on Basic Aspects of Fast Atom Bombardment Mass Spectrometry Matrix Effects, Sample Effects, Sensitivity and Quantification, Biomed. Mass Spectrom., 11, 217, 1984. 

Photolysis of the crystals or powdered samples resulted in the alternating copolymerization of 32 and 33 as confirmed by fast-atom bombardment mass spectrometry. 

Tetracycline antibiotics have been determined in bovine liver, kidney, and muscle, and in milk by solid-phase extraction followed by TLC7MS with FAB mass spectrometry (45,46). A reverse-phase C8 bonded phase silica TLC plate was used. Adjacent lanes of standards provided Rf values for the compounds of interest. This area of the chromatogram was cut into a trapezoidal shape, and additional solvent concentrated the sample in one end of the shape. That portion of the chromatogram was then placed on the FAB probe of a high-performance mass spectrometer. Then, the FAB support matrix (thioglycerol) was added to the plate. A detection limit of 0.1 microgram of sample per spot was reported for most of the tetracycline antibiotics. The trapezoidal slice from the TLC plate used to concentrate the sample for TLC/MS analysis was also used in an application of fast atom bombardment mass spectrometry to identify and quantitate the drug midazolam (a depressant and anaesthetic) in plasma extracts by Okamoto et al. (47). 

Peirce, P., Hambidge, K., Goss, C., Miller, L., and Fennessey, P. (1987) Fast-atom-bombardment mass spectrometry for the determination of zinc stable isotopes in biological samples. Anal. Chem., 59, 2034-2037. 

Several recently developed techniques to enhance sample desorption capitalize on the transfer of kinetic energy to the sample through molecular collisions to produce desorbed positive and negative ions as well as desorbed neutral molecules. The more useful of these bombardment techniques include secondary ion mass spectrometry (SIMS), fast atom bombardment mass spectrometry (FAB-MS), and californium-252 plasma desorption mass spectrometry (252 Cf-MS). The sample can be deposited on an inert surface and directly bombarded in the solid state, or more commonly it is dissolved (or suspended) in an inert and nonvolatile medium such as glycerol. 

Sample preparation Condition a 3 mL 200 mg Bond Elut CIS SPE cartridge with two 3 mL portions of MeOH and two 3 mL portions of 5% acetic acid. Mix 500 p,L serum with 500 p.L 10% acetic acid, add to the SPE cartridge, wash with 3 mL water, elute with four 500 p,L portions of MeOHrwater 60 40. Evaporate the combined eluates to dr3mess under a stream of nitrogen, reconstitute the residue with 250 iL water, filter (0.22 p,m). Inject a 100 p,L aliquot onto column A and elute to waste with mobile phase A. After an unspecified time, backfiush the contents of column A onto column B using mobile phase B. Monitor the effluent from column B. (Sato,K. Kobayashi,K. Moore, C.M. Mizuno,Y. Katsumata,Y. Semi-quantitative analysis of cefaclor in human serum by capillary high performance liquid chromatography/fast atom bombardment mass spectrometry. Forensic Sci.Int. 1993, 59, 71-77.)... 

These techniques are discussed together because the principles behind them are similar. In secondary ion mass spectrometry (SIMS) (79), the ions are produced by bombarding the sample molecules with a beam of fast ions. When the ion beam is replaced by a beam of fast atoms the technique is called fast atom bombardment mass spectrometry (FABMS) (20). Introduced in its modern form by Barber and co-workers (27), FABMS has proved a versatile method for examining natural products. The production of ions in FABMS is illustrated in Fig. 1. 

Extra-framework aluminium gradients. The surface of SiCl4-dealuminated zeolite crystals is sometimes enriched with aluminium, as detected with X-ray Photoelectron Spectroscopy (ref.35) and Fast Atom Bombardment Mass Spectrometry (ref.36). In the samples of Kubelkova et al. the surface Si/Al ratio did not exceed twice the bulk ratio (ref.35). van Broekhoven et al. prepared zeolite Y samples with 27 and 17 Al /UC in which no surface enrichment was found (ref.55). From the available data it is not possible to derive whether the accumulation of aluminium at the surface takes place during the SiCl4 treatment or is the result of migration during washing. 

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