ION-TRAP MASS-SPECTROMETRY WITH AN INDUCTIVELY-COUPLED PLASMA SOURCE

A new mass spectrometry technique using an inductively coupled plasma (ICP) ionization source and an ion-trap mass spectrometer (ITMS) detector is described and evaluated for elemental and isotopic analysis. Initial results obtained with the ICP-ITMS technique include sub-ppb detection of bare ions for most elements, complete destruction of typical polyatomic matrix ions (e.g., ClO+, ArO+, and ArCl+), and effective neutralization of strong Ar+ ion currents. The latter effects allow observation of clearer mass spectra at m/z < 80 and potentially improved detection of 'problem' elements in ICP-MS (e.g., K, Ca, V, Fe, As, and Se). Formation of poly-oxide and -hydroxide ions of metals with high oxide bond strengths were observed and require system modifications to alleviate.