Polyatomic ions as internal standards for matrix corrections in inductively coupled plasma mass spectrometry

Several strong polyatomic ion signals common in inductively coupled plasma mass spectrometry can be used as internal standards to correct for matrix interferences. Signals for most of the polyatomic ions, including metal oxides, are suppressed by a Cs matrix to the same extent as analyte ion signals at nearby m/z values. Examples include 14N2+ and 24Mg+, 35Cl16O+ and 55Mn+, 40Ar16O+ and 59Co+, 32S16O+ and 45Sc+, 40Ar2+ and 75As+, and 89Y16O+ and 103Rh+. The count rates for these polyatomic ions are often measured anyway to determine interference corrections for spectral overlap, so these signals should reduce the number of added elements necessary to correct for matrix interferences.