Complex samples and spectral interferences in ICP-MS: Evaluation of tandem mass spectrometry for interference-free determination of cadmium, tin and platinum group elements

Abstract

An analytical method was developed for determination of Cd, Sn, Pd, Pt and Rh in sediments, fertilizer and sludge samples by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The performance of ICP-MS/MS using oxygen into the octopole reaction system (ORS3) and MS/MS mode, on mass and shift mass, was evaluated to overcome spectral interferences. Addition and recovery experiments in sediments, fertilizer and sludge samples at three concentration levels, 0.5, 1.0 and 5.0μgL−1, were carried out to evaluate the accuracy of the developed procedure. Quantitative recoveries, from 80 to 113% for 112Cd+, 120Sn+ and 106Pd+ were reached using MS/MS in on mass operation mode. For Pt and Rh, recoveries ranged from 81 to 117% by monitoring 195Pt16O+ and 103Rh16O+ in MS/MS (shift mass mode) with 0.3 mL min−1 oxygen gas flow rate pressurized into the ORS3. Limits of detection of the developed method were 15, 2.5, 1.8, 9.0 and 9.9μgkg−1 for 195Pt16O+, 103Rh16O+, 112Cd+, 120Sn+, and 106Pd+, respectively. All analytes were simultaneously interference-free determined by ICP-MS/MS, which demonstrates the potential of this instrumental analytical strategy for Cd, Sn, Pd, Pt, and Rh determination in complex samples.