Overcoming interferences in inductively coupled plasma mass spectrometryvia gas-flow modulation Part 2. Correlation methods

Abstract

The second of two methods for reducing oxide interferences in inductively coupled plasma mass spectrometry is outlined. In both methods, manipulation of the central-channel gas flow generates unique behavior from analytes and interfering oxides that can subsequently be used to isolate signal contributions from both species superimposed at a given mass. Here, mathematical correlation between an interferent-compromised analyte response and an internal standard allows errors from troublesome interferences to be effectively eliminated. This correction method is capable of addressing multiple analyte–oxide interferences without sacrificing analyte sensitivity. A time-of-flight mass analyzer was used in this work to provide multi-elemental capabilities; however, the method is amenable to implementation on other simultaneous or scan-based mass analyzers.