Abstract

Isotope ratio measurements are typically accomplished by methods that are seldom amenable to field use. An example is thermal ionization mass spectrometry (TIMS)i where solid samples are dissolved, a filament loaded with the resulting solution, the filament mounted in a source chamber, the mass spectrometer pumped to low pressure, the filament heated to produce analyte ions, and finally the ions separated according to mass in either space or time for counting. There is a need for field mass spectrometric measurements, particularly in the environmental remediation arena, where near real time results can save time and reduce costs. Miniaturized ion traps that can be deployed for field measurement of organics have been reported. 2 There currently are no isotope ratio methods in field use.

© 1994 Optical Society of America