Optimization of sample preparation and ICP-MS analysis for determination of 60 elements for characterization of the plant ionome

Abstract

An ICP-MS method for determination of 60 elements in plant samples is proposed based on optimization of digestion, recommending use of HF besides HNO3 and H2O2 and calibration procedures, using CRMs for construction of calibration curves. Adequate choice of analytical isotopes and various measurement conditions (cold plasma for the determination of Al, Ba, Ca, Fe, K, Mg, Mn, Na, Si and Sr and DRC mode for determination of Ag, As, Ni, Pd, Pt, Se and V) as well as introduction of appropriate corrections lead to determination of as large number of elements with quadropole ICP-MS as with the more expensive SF-ICP-MS. Two measurements are performed: cold plasma and standard/DRC mode. The analytical characteristics of the method are demonstrated by analysis of five CRMs and the agreement of the experimental results with the certified/information/literature values is very good. Detection limits are low enough to permit the determination of all elements but platinum metals at background level. The applicability of the method is demonstrated by analysis of Taraxacum officinale (dandelion) samples collected from regions with different anthropogenic influence. The results indicate high degree of pollution round the Pb-Zn smelter with As, Cd, Cu, Ni, Pb and Zn and increased concentrations of B, Be, Bi, Hg, In, Mn, Sb, Se, Sn, Ti, Tl, V and Zr. The dandelion sample, collected along a highway has increased concentrations of traffic released elements: Pt, Pd, Rh, Ce, La, Pb as well as Cu, Zn, Ba and Rb.