MIKE scan techniques

These examples show the applications of MIKE method. In the same way, linked scan techniques may be particularly valuable. These methods are rapid, thus allowing the accumulation of iterative results, since there is a satisfying reproducibility. 

Thus, scanning of the electric field E scan) yields an energy spectrum which allows for the determination of the kinetic energy release (KER) from the peak width (Chap. 2.8.2). The MIKE technique provides good precursor ion resolution, but poor product ion resolution according to the influence of KER on peak shapes. 

A similar technique applicable to reverse geometry mass spectrometers (magnetic sector before electrostatic analyser) is that of mass-analysed ion kinetic energy spectrometry (MIKES). In this technique the ion to be studied is isolated by the magnet and induced to fragment by collision activation in a small chamber filled with a gas such as helium. The product ions are then detected by scanning the electrostatic analyser voltage. 

These relatively old examples of using classic metastable ion spectra for determining molecular structure remain minor. Also, certain aspects, such as the study of mixtures, must be approached with different techniques, such as ionization, even the most recent, or metastable ion detection with BjE (or B /E) linked scan and MIKE methods. 

The MIKE and BjE linked scan modes were compared in this study (Fig. 108) and the authors noted that each technique has its advantages and drawbacks. BjE furnishes good resolution of secondary ions (as daughters) while MIKE leads to a better resolution of primary ions (as precursors). 

A simple and inexpensive way of obtaining MS/MS information is the use of linked scans in sector field instruments. The advantage over the MIKES technique is that the resolution is generally better and that all double-focusing instruments can be used. The two sectors and the acceleration voltage are linked together by functions that allow... 

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