Using Ion–Molecule Reactions To Overcome Spectral Interferences in ICP-MS: A Guided Inquiry Approach for Upper-Level Undergraduate and Graduate Students

Almost all commercial quadrupole ICP-MS instruments use collision/reaction cells to either attenuate spectral interferences or shift the analyte of interest to an interference-free m/z (e.g., by O addition). A laboratory practical was developed to introduce the students to the basic operating principles of ICP-MS using a hands-on approach, with an emphasis on practical strategies for the effective use of reaction cells in ICP-MS. Vanadium, and the ClO+ diatomic interference formed in HCl matrixes, was used as an illustrative example, which enabled students to explore charge transfer, clustering, condensation, and oxygen atom addition reactions of a single analyte, and evaluate the most effective approach for the chemical resolution of V+ and ClO+ ions. This laboratory practical provided graduate students with a basic skill set to support the effective use of ICP-MS with reaction cell technology in their research projects.