Editor's Column
In next month's Instrumentation Column, Peter H. Dawson of C.R.A.M., Université Laval, and J. W. Hedman and N. R. Whetten of General Electric Co. will describe a new miniature mass spectrometer which weighs less than 2 oz. The new instrument operates on the ion storage principle, with the ions being mass-selectively trapped in the volume enclosed by the electrodes, and it can analyze the composition of gases in dilute concentrations where the total pressure may be 1015 times less than normal atmospheric pressure. The detection system is based on a conventional electron multiplier. Half-height mass resolutions of up to 150 have been achieved. The miniature mass spectrometer has potential applications in process control, extraterrestrial analysis, medicine, environmental monitoring, geology, and reaction studies. Instrumentation based on the design should cost only several hundred dollars—as opposed to the many thousands of dollars which much larger conventional mass spectrometers now cost. At the National Institutes of Health Symposium on Recent Developments in Research Methods and Instrumentation, October 5—9, 1970, James Ross of Orion Research, Inc., will discuss the possibility of adapting ion-selective microelectrodes for continuous monitoring and automatic sequential analysis of samples for ions of immediate biological interest, such as Na + , K + , Ca 2 +, Mg 2 + , C I - , and I - . His goal is ultimicromeasurements of very small samples. Clearly, miniaturization provides a possible means of reducing space and cost requirements for an increasing amount of analytical instrumentation. Miniaturization also allows the analysis of some systems too small to be handled conveniently by larger instruments. It certainly is worth looking into when considering the purchase of a new analytical instrument. Alan J. Senzel
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ANALYTICAL CHEMISTRY, VOL. 42, NO. 11, SEPTEMBER 1970
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