Reduction of polyatomic interferences in biological material using dynamic reaction cell ICP-MS

An analytical method is described for the routine quantification of five elements (As, Cr, Fe, Ni, and Se) in plants and animal feedstuffs using dynamic reaction cell inductively coupled plasma mass spectrometry (ICP-DRC-MS) after microwave digestion. Methane (for Cr, Fe, Ni, and Se) and oxygen (for As) were used as reaction gases to reduce polyatomic interferences. Optimization of the gas flow rate and the quadrupole dynamic bandpass tuning parameter (RPq) was carried out for the method. Detection limits (LOD) were in the range of 0.03–0.65 µg L− 1 and were significantly lower compared to the standard mode without DRC. The trueness of the method was tested using three reference materials from Round robin tests. Results were well in accordance with the certified values. Furthermore, DRC data were examined by analyzing the same samples using sector field ICP-MS (SF-ICP-MS) and an ICP-MS equipped with collision cell technology (ICP-CCT-MS). The data obtained were in the confidence range of the reference material, too. The investigated method was applied for the analysis of grass and corn silage samples.