Multi-isotope Calibration for Determination of Nickel, Molybdenum, Barium and Lead in Soil Samples by Inductively Coupled Plasma Mass Spectrometry

The multi-isotope calibration is a fast and accurate calibration strategy for multi-elemental determination that uses only two solutions, (1) 50% (v v(-1)) sample plus 50% (v v(-1)) analytical blank solution, and (2) 50% (v v(-1)) sample plus 50% (v v(-1)) standard solution (containing the analytes). The concentration of the analytes was calculated from the slope and the concentrations of the standards were added to solution 2. The validation of the method was evaluated using five standard reference materials of soils. The conventional internal standardization was also evaluated for comparative purpose. Low limits of quantifications and good linearity for calibration curves were achieved for all the evaluated elements. The values were 0.022, 0.026, 0.019, and 0.017 mu g L-1 for Ni, Mo, Ba, and Pb, respectively.