Mass spectrometry sector instruments

In mass spectrometers, ions are analysed according to the ml7. (mass-to-charge) value and not to the mass. While there are many possible combinations of technologies associated with a mass-spectrometry experiment, relatively few forms of mass analysis predominate. They include linear multipoles, such as the quadrupole mass filter, time-of-flight mass spectrometry, ion trapping forms of mass spectrometry, including the quadrupole ion trap and Fourier-transform ion-cyclotron resonance, and sector mass spectrometry. Hybrid instruments intend to combine the strengths of the component analysers. 

Mass Spectrometry of Small Molecules Magnetic-Sector Instruments 409... 

Polymer/additive analysis greatly benefits from high-resolution mass data, which often leads to unambiguous identification of (known) additives. However, the investment and operating costs of this instrument do not easily justify its (exclusive) use for the purpose of routine polymer/additive analysis. Analysis of organic polymer additives by means of mass spectrometry is aided by the utilisation of precursor ion and second-generation product ion (MS3) scanning experiments [169], A four-sector... 

R. S. Bordoli, K. Howes, R. G. Vickers, R. H. Bateman, and D. J. Harvey. Matrix-Assisted Laser Desorption Mass Spectrometry on a Magnetic Sector Instrument Fitted with an Array Detector. Rapid Commun. Mass Spectrom., 8(1994) 585-589. 

Isotopic mass spectrometry is used to establish 813C values. The sample is burned to C02 and the intensities of the ion peaks of m/z 44, 45, and 46 are measured. Then correction to eliminate the influence of 170 isotope is achieved. If using sector magnetic instrument and three detectors (for each mass) the standard deviation of the results will be better than 0.001%. The high accuracy of the measurements allows valuable results to be obtained. The ancient Europeans and Americans may be distinguished by the analysis of their remnants. The reason involves the fact that wheat constituted the basic food ration in Europe, while com played the same role in America. The difference in the isotopic composition of these plants forms several units of 813C scale [34],... 

From the 1950s to the present mass spectrometry has changed tremendously and still is changing. [12,13] The pioneering mass spectrometrist had a home-built rather than a commercial instmment. This machine, typically a magnetic sector instrument with electron ionization, delivered a few mass spectra per day, provided sufficient care was taken of this delicate device. If the mass spectrometrist knew this particular instrument and understood how to interpret El spectra he or she had a substantial knowledge of mass spectrometry of that time. [14-18]... 

In general, the quadrupole instruments do not achieve the mass range and the high resolution of sector instruments. However, the mass range and resolution are adequate for unit-resolution mass spectrometry, and the rapid scan and sensitivity make them especially suitable for use with capillary gas chromatography (Fig. 2.46). 

A quite different type of mass spectrometer - the first 180° magnetic sector field mass spectrometer (see Figure 1.7), with directional focusing of ions for isotope analysis, was constructed by Dempster, independently of other instrumental developments in mass spectrometry, in 1918. 

Today there are a number of mass spectrometer companies producing a wide variety of different types of quadrupole-based, sector field and ToF instruments for quite different applications in the trace, ultratrace, isotope and surface analysis of inorganic materials and for the structural analysis of organic and bioorganic compounds. Mass spectrometry for the structural analysis of organic compounds including large biomolecules is described elsewhere. 

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