Abstract

The dynamic reaction cell (DRC) is a rf/dc quadrupole which may be pressurized with a reactive gas in order to promote ion–molecule reactions intended to suppress plasma-based isobaric interferences for trace elemental analysis. The bandpass of the DRC is adjusted in order to suppress the appearance of new interferences produced through sequential reactions within the reaction cell. The DRC may alternatively be operated at low pressure (vented, under collision-free conditions) to emulate conventional ICP-MS. A practical optimization procedure for both the vented and pressurized modes is described, with examples showing the suppression of both plasma-based and cell-based isobaric interferences. The analytical performance characteristics of the instrument, including efficiency of isobar rejection, detection limits in clean water and in neat hydrogen peroxide, short- and long-term stability, determination of arsenic in chloride solution and Se isotope determination, are provided.