Analytical instrument health check

Abstract

An analytical instrument comprises an analyser and an atmospheric pressure ion source configured to generate analyte ions in an ionisation region. A method of checking the operational state of the analytical instrument comprises generating reference ions by introducing vaporised molecules or molecule clusters of a reference compound into the ionisation region such that at least some of the vaporised reference compound molecules or molecule clusters are ionised in the ionisation region by the atmospheric pressure ion source, detecting, using the analyser, at least some of the reference ions or ions derived from the reference ions, and determining an operational state of the analytical instrument based on the detection.

Dependencies are inferred from the claim text.