Mass analyzers costs

The choice of a mass spectrometer to fulfill any particular task must take into account the nature of the substances to be examined, the degree of separation required for mixtures, the types of ion source and inlet systems, and the types of mass analyzer. Once these individual requirements have been defined, it is much easier to discriminate among the numerous commercial instruments that are available. Once suitable mass spectrometers have been identified, it is then often a case of balancing capital and running costs, reUability, ea.se of routine use, after-sales service, and manufacturer reputation. 

Achieving high resolving power and high m/z measurement accuracy is one way of decreasing uncertainty when the determination of unknown analyte identity is the object of an experiment. But like many techniques, an increase in experimental or interpretive confidence does not come without some cost (e.g., instrument size, complexity, price, etc.). However, exact m/z measurements (and their associated elemental formula information) are but one type of information that can be derived from mass spectrometers. In the sections that follow, a variety of mass analyzers will be described in terms of their basic principles, functionality and applications. 

In order for an instrument to carry out MS-MS, it must be able to do the three operations outlined above. As we have seen however, ion-trap systems capable of MS-MS and MS(n) do not use a tandem arrangement of mass analyzers at all, but rather use a single ion trap for all three operations simultaneously. As has already been stated, these ion-trap tandem mass spectrometer experiments are very sensitive and are now user friendly. The ion trap brings the capability for carrying out MS-MS experiments to the benchtop at relatively low cost. 

ICP-MS elevated cost (although less than most molecular MS instrumentation), possibly troublesome polyatomic interferences, low ionization efficiency for biologically important elements (Se, S, P, halogens), and, in most commercially available instruments, sequentially scaiming nature of mass analyzer and detection system. 

Since the difference in cost would be very large, there would be no difficulty in making a choice. However, just as defining boundaries between gases, liquids, and solids is a tenuous exercise in the face of considerations of vacuum, volatility, and thermal stability, so the choice of mass analyzer can become a difficult one. 

Mass analyzer Measures Upper mass Resolving power Accuracy (ppm) Dynamic rangea Cost ... 

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