The Analytical Chemistry Community recognizes the power of the mass spectrometer as an analysis tool and envisions applications that would require miniature instrumentation. In recent years, there has been significant research directed at developing a miniature cylindrical ion trap (CIT) for use as an analyzer in a mass spectrometer. This research was conducted primarily by Professor. R. Graham Cooks at Purdue University and Dr. J.M. Ramsey at Oak Ridge National Laboratory.
These two respected researchers have focused on studying the CIT with regard to specific fundamental advantages the analyzer offers relative to other related technologies. The cylindrical ion trap is a simplified version of a quadrupole (It is spelled correctly it is 4 poles) ion trap, an instrument that is commercially available for laboratory experimentation. The key characteristic of this type of analyzer is its capacity to perform multidimensional mass analysis, as stated above.
Conventional ion trap instrumentation has complex components that are not easily miniaturized. By simplifying the ion trap to create the CIT (shown in Figure 2.), a much smaller ion trap can be constructed. The importance of miniaturizing the mass analyzer is increased by the fact that the size of the analyzer is inversely related to the voltage required to perform an
analysis. The power supplies used to operate conventional ion trap mass
analyzers generate thousands of volts and occupy a substantial fraction of
the full instrument’s volume. The smaller CIT requires substantially less
power and physically smaller electronics, further aiding in instrument
miniaturization. Figure 3 shows the results of miniaturization of the
analyzer and its associated ion optical elements.
Another advantage of the CIT analyzer is that is it can operate at a higher
pressure than competitive mass spectrometer-based technologies (all mass
spectrometers require high vacuum). It is important to minimize the vacuum
requirements for a portable instrument, as the vacuum pumps can be the
largest, most power consuming, and most fragile components of a mass
spectrometer. Fragile components of a mass\par
spectrometer.
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