Spectral Interferences of Some Polyatomic Ions in the Determination of Traces of Platinum Metals and Gold in Geological Samples by Inductively Coupled Plasma Mass Spectrometry

To improve the accuracy of determining low (ng/g) concentrations of noble metals (Au, Pd, Pt, Rh, Ru, and Ir) in geological samples, we experimentally assessed mass spectral overlapping due to certain rock components. It was found that the ion exchange separation of the matrix does not eliminate the interferences from Zr, Hf, and Ta oxides, and in some cases, the complete removal of these elements from the test solution is required. An analysis of SRMs SChS-1, SLg-1, TDB-1, OPY-1, and SBC-1 demonstrated that the use of a Ln-resin as an additional sorbent in combination with the subsequent ICP–MS determination in the low and/or medium resolution mode offers promise.