Analytical performance of the plasma source RF quadrupole ion trap in elemental and isotopic MS

Abstract

Recent progress in the development of ion trap ICP-MS instrumentation is presented in terms of performance figures of merit for trace elemental and isotopic analysis. Conventional polyatomic ion interferences are avoided altogether using collisional dissociation techniques inherent to ion trap operation. The current detection limits are in the low pg mL^–1 range, as obtained over extended mass scans using multi-element solutions. The dynamic range linearity is nearly six orders of magnitude using variable injection times to control ion density in the trap. The abundance sensitivity is 10⁵ to 10⁶ using selective ion monitoring. Other performance figures approach or exceed those of conventional linear quadrupole based ICP-MS instrumentation.

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