Mass spectrometry advantages

Titration and Mass Spectrometry, Advantages. This method allows high-sensitivity, low background, quasi-continuous measurements, is amenable to all present external calibration methods, and has been successfully compared with LPA. 

CHEMICAL ELEMENTS IN FOOD AND THE ROLE OF ATOMIC AND MASS SPECTROMETRY. ADVANTAGES AND DRAWBACKS OF THE DETERMINATION OF SELECTED TRACE ELEMENTS IN FOODSTUFFS BY ATOMIC ABSORPTION SPECTROMETRY... 

Figure 6 Schematic diagram of online coupling LC-ICP-MS via conventional nebulization and via microwave (MW)-HG. (Reprinted from Gonzalez LaFuente JM, Marchante Gayon JM, Fernandez Sanchez ML, and Sanz-Medel A (1999) Urinary selenium speciation by high-performance liquid chromatography-inductively coupled plasma mass spectrometry advantages of detection with a double focussing mass analyser with a hydride generation interface. Talanta 50 207-217.)...

Gas chromatography-mass spectrometry Advantages of GC-MS over traditional methods that use multiple element selective detectors include (1) simultaneous quantitation and confirmation of detected analytes (2) detection of a wide range of analytes independent of elemental composition (3) possibility to spectrometrically resolve (deconvolute) coeluting peaks and, as a consequence, (4) reduced personnel, laboratory space, and instrumentation needs, and (5) increased sample throughput. On the other hand, GC-MS instruments are still more expensive than GC instruments with element selective detectors, and sometimes, in very complex matrices, element selective detectors may permit detection of lower concentrations of residues masked by matrix interferences in GC-MS. 

McLean, J. A., Ridenour, W. B., Caprioli, R. M. (2007) Imaging ion mobility mass spectrometry advantages, challenges, and future prospects. Proceedings of the 55th Annual Meeting of the American Society for Mass Spectrometry, Indianapolis, IN. 

Appelblad, P.K., Rodushkin, 1., and Baxter, D.C. (2000) The use of Pt guard electrode in inductively coupled plasma sector field mass spectrometry advantages and limitations. J. Anal. At. Spectrom., 15, 359-364. 

Smith, C.W. (1991). Analytical Inductively Coupled Plasma Mass Spectrometry Advantages, Limitations, Research Directions and Applications, a Literature Review, Div. rep., MSL 91-72 (LS). Mineral Sciences Laboratories, Ottawa. 

Turner, P. 1., Mills, D. 1., Schroder, E., Lapitajs, G., Jung, G., lacone, L., Haydar, G., and Montaser, A. (1998) Instrumentation for low and high-resolution ICP-MS. In Inductively Coupled Plasma Mass Spectrometry (ed. A. Montaso"), WUey-VCH, New York, pp. 422-94. Appelblad, P. K., Rodushkin, I., and Baxte, D. C. (2000) The use of PT guard electrode in inductively coupled plasma sector field mass spectrometry advantages and limitations. J. Anal. At. Spectrom., 15(4), 359-64. 

Note that in mass spectrometry/mass spectrometry (MS/MS) applications, quadrupole and magnetic sectors can be used together advantageously. It is also worth noting that the quadrapole can be operated without the DC voltages. In this RF-only mode, no mass separation occurs, and these quadrapoles are used as ion transmission guides, described in Chapter 49. 

Liquid chromatography/mass spectrometry (LC/MS) is an analytical technique combining the advantages of an LC instrument with those of a mass spectrometer. 

Gas Chromatography (gc). A principal advantage of gas chromatography has been the faciUty with which it can be combined with mass spectrometry for amino acid identification and confirmation of purity. The gc-mass spectrometry combination offers the advantage of obtaining stmctural information rather than the identification by retention time in hplc. 

The main advantages of the ms/ms systems are related to the sensitivity and selectivity they provide. Two mass analyzers in tandem significantly enhance selectivity. Thus samples in very complex matrices can be characterized quickly with Htde or no sample clean-up. Direct introduction of samples such as coca leaves or urine into an ms or even a gc/lc/ms system requires a clean-up step that is not needed in tandem mass spectrometry (28,29). Adding the sensitivity of the electron multiplier to this type of selectivity makes ms/ms a powerhil analytical tool, indeed. It should be noted that introduction of very complex materials increases the frequency of ion source cleaning compared to single-stage instmments where sample clean-up is done first. 

The use of separation techniques, such as gel permeation and high pressure Hquid chromatography interfaced with sensitive, silicon-specific aas or ICP detectors, has been particularly advantageous for the analysis of siUcones in environmental extracts (469,483—486). Supercritical fluid chromatography coupled with various detection devices is effective for the separation of siUcone oligomers that have molecular weights less than 3000 Da. Time-of-flight secondary ion mass spectrometry (TOF-sims) is appHcable up to 10,000 Da (487). 

The recent development and comparative application of modern separation techniques with regard to determination of alkylphosphonic acids and lewisite derivatives have been demonstrated. This report highlights advantages and shortcomings of GC equipped with mass spectrometry detector and HPLC as well as CE with UV-Vis detector. The comparison was made from the sampling point of view and separation/detection ability. The derivatization procedure for GC of main degradation products of nerve agents to determine in water samples was applied. Direct determination of lewisite derivatives by HPLC-UV was shown. Also optimization of indirect determination of alkylphosphonic acids in CE-UV was developed. Finally, the new instrumental development and future trends will be discussed. 

For off-bead analysis, coupling between chromatographic separation and mass spectrometric detection has proven especially powerful. The combination between high performance liquid chromatography (HPLC) and electrospray ionisation mass spectrometry has the advantage that purity of product mixtures can be coupled on-line with the product identification. 

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