Analytical performance of axial inductively coupled plasma time of flight mass spectrometry (ICP-TOFMS)

Abstract

Analytical performance of an axial ICP-TOFMS, in terms of accuracy, precision, resolution, signal stability, repeatability, reproducibility, precision of isotope ratios and detection limits is reported. Cool plasma conditions (low power and high central gas flow) allow the determination of K, Ca and Fe at trace levels. Detection limits for 64 elements are reported with typical values from 0.5–20 pg ml^–1 (3 s criterion). The long-term stability over 4 h for the raw signal ranges between 1.0% RSD for ⁷Li to 2.1% RSD for ⁴⁰Ca operating under cool plasma conditions. Under normal plasma conditions the corresponding values are 6.9% RSD for ²⁰⁸Pb to 12.8% RSD for ⁵⁹Co. Accuracy for the determination of 16 different elements is assessed by measuring NIST 1643d (trace elements in water), yielding results in agreement with certified values. Results for isotopic ratio determinations demonstrate that a precision of 0.07–0.7% RSD is obtained within a short data acquisition period.