Magnetic sector analyzer principle

The most commonly used mass separators are quadrupoles, ions traps and time-of-flight analyzers, for which the principle of mass separation is discussed below. Additionally, other types such as magnetic sector field or Fourier-trans-form cyclotron-resonance instruments are available. 

Once analytes pass through the ion source, they move into the mass analyzer. The two common mass analyzers for GC are the magnetic sector and quadrupole. Also available but less common are time-of-flight (TOF), triple quadrupole, and ion trap. The purpose of all of these devices is to separate ions according to their m/z ratios. The principles behind the most common mass analyzers have been described above in the section entitled HPLC-MS and HPLC-MS/MS . The mass analyzer separates the ions, which are then sent to the detector. The most common detector is the electron multiplier, which involves... 

In this chapter the principles of various mass analyzers were enumerated. The function of a mass analyzer is to disperse all ions (in space, time, or frequency) in terms of their miq ratio. This work is accomplished by manipulating their momentum, kinetic energy, and velocity. Magnetic-sector instruments are one... 

Tbe reader new to mass spectrometry is advised to consult an appropriate introductory text [2-9]. A few mass spectrometric terms will be explained here by way of background and to outline the principles of choosing a flame ionization detector, ions are produced in the mass spectrometric detector, but the mass spectrometer is able to analyze these ions further according to their molecular weights or rather, mass-to-charge ratios (m/z, see below) to provide a mass spectrum. Different principles are employed to achieve this in a variety of types of mass spectrometer. The instruments most commonly used in GC—MS are known as magnetic sector, quadrupole and ion trap mass spectrometers. Their differences are not further described here. Bench-top systems are of the quadrupole or ion trap type. 

The mass analyzers most commonly used in the SSIMS technique are magnetic sector, quadrupole, and time-of-flight (TOE) analyzers. The TOE analyzer is based on the principle that ions with different mass/charge ratios will travel a fixed path length in different limes, when they are accelerated through the same potential field. The lighter ions travel at a faster velocity and are thus detected before the heavier ions. Compared to the other mass... 

Magnetic sector and time-of-flight (TOP) analyzers are used less frequently in GC-MS coupling their functioning principles and advantages are described briefly at the end of this chapter. 

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