MIKES mass-analyzed ion kinetic

MIKES. mass-analyzed ion kinetic energy spectroscopy... 

Certain quinazolines, e,g. l-methylquinazolin-4(l//)-one, fragment by a retro-Diels-Alder process. The MIKE (mass analyzed ion kinetic energy) spectrum of the molecular dication of quinazoline is very similar to that of quinoxaline. MIKE spectra of quinazolinethiones show the loss of NCS radicals from the molecular ionA ... 

In sector instruments with reversed geometry, product ion scanning as depicted above is known as MIKES (mass-analyzed ion kinetic energy spectrometry). The magnet is used to select the precursor... 

The structure of the radical cation [CaHsN] (102) has been established by mass-analyzed ion kinetic energy spectrometry (MIKE) (780MS518). From structure (103), structures (104) and (105) are formed (Scheme 4). 

Mass-analyzed ion kinetic energy spectra (MIKES) [85,86] can be measured on BE geometry instruments only. The precursor ion is selected by the magnet and the fragments from dissociations of in the 2.FFR are analyzed by the ESA due to their kinetic energy. This is possible, because the kinetic energy of the precursor is distributed among the product ion and the neutral. Derived from Eq. 4.10 we have... 

Beynon, J.H. Cooks, R.G. Amy, J.W. Baitinger, W.E. Ridley, T.Y. Design and Performance of a Mass-Analyzed Ion Kinetic Energy (MIKE) Spectrometer. Anal Chem. 1973,45, 1023A. 

A number of methods have been described for determination of tetracycline (chlortetracycline, tetracycline, and oxytetracycline) residues in tissues of food-producing animals (53-62), fish (63), eggs (64), and honey (65,66). Most of these methods use reversed-phase HPLC for determination. However, one uses TLC with UV densitometry ( ) and one uses GLC ( ), and one uses a direct mass spectrometric method CAD MIKE spectrometry (collisionally activated decomposition mass-analyzed ion kinetic spectrometry) for oxytetracycline in milk and meat (62). Several use solid-phase extraction in the cleanup procedure using XAD-2 resin (56,58) or Cj g cartridges... 

The most recent metastable defocusing technique, which is referred to as mass-analyzed ion kinetic spectroscopy (MIKES) by Beynon (77, 270, 277) and as direct analysis of daughter ions (DADI) by Maurer (278) requires the interchange of the source and collector positions in a double-focusing mass spectrometer of Nier-Johnson geometry. With... 

Fig. 7. Mass-analyzed ion kinetic energy (MIKE) spectra of C6FsSi(CH3)3. [Reproduced with permission from J. M. Miller, J. Ross, J. Rustenberg, and G-. L. Wilson, Anal. Chem. 45, 627 (1973) copyright by the American Chemical Society.]...

Mass spectrometry is suitable for the identification of pyrrolo-benzodiaze-pines and the differentiation of their isomers (1996M1653). A structural distinction can be made easily from their mass spectra or the metastable mass-analyzed ion kinetic energy (MIKE) spectra, produced by their molecular or most intense fragment ions. Established fragmentation pathways have been supported by MNDO and AMI semiempiiical calculations. 

TD-IT, Thermal desorption-ion trap CAD MIKE, collisionally activated decomposition mass-analyzed ion kinetic energy MID, multiple ion detection FID, flame ionization detector NPD, nitrogen/phosphorus detector SIM, selected ion monitoring El, electron impact TMS, trimethylsilane MTBSTFA, N-methyl-N-(tetr.-butyldimethylsilyl)trifluoroacetamide. 

In electron impact (El) mass spectra PCDTs show a strong molecular M1 ion and the expected clustering due to chlorine and sulfur isotopes. The major difference in the El mass spectra of the PCDDs and PCDTs is the formation of a strong M+-COCl in the former and a strong M+-2C1 in the latter compounds. PCDDs and PCDFs could be detected with good sensitivity via the reaction M+— (M-COCl)+ by QUAD MS/MS. Mass-analyzed ion kinetic energy (MIKE) MS/MS was found suitable for detecting the PCDTs via the reaction M+ —> (M-2Cl)+, whereas PCDDs and PCDFs were monitored by the reaction M+ —> (M-COCl)+ [31]. 

Kemp, D. L., Cooks, R. G. and Beynon, J. H. Simulated mass-analyzed ion kinetic energy (MIKE) spectra from a conventional double focusing mass spectrometer. Int.. Mass Spectrom. Ion Phys. 21 93-101, 1976. 

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