Effects of sample preparation and calibration strategy on accuracy and precision in the multi-elemental analysis of soil by sector-field ICP-MS

摘要: Soil samples were prepared for multi-element analysis using HNO3 leaching or pseudo-total digestion with HNO3, HCl and HF in a microwave oven, both methods requiring 70 min heating time. Two calibration approaches the soil characterization also compared: external calibration, combined internal standardization, isotope dilution (ID) after appropriate spiking of soils stable mixture prior to sample preparation. Analyses performed inductively coupled plasma sector field mass spectrometry (ICP-SFMS). Accurate total elemental concentrations only obtained Cd P preparation two certified reference materials, NIST SRM 2709 CCRMP SO-2, as well comparable values Finnish inter-laboratory soil. The method provided accurate results As, Be, Co, Fe, Mn, Ni, Pb, Sb, Ti, V Zn. For Cu SO-2 Cr incomplete recoveries always obtained. In case Cr, this is due difficulties associated complete solubilization refractory minerals. given final factor, provides better limits detection (LODs) than ID. As quantification yield essentially equivalent accuracy precision, be preferred greater number elements are amenable shorter measurement On other hand, ID can matrix separation (NH3 precipitation was used here), allowing lower factors without deleterious effects on instrumental performance. particular, improved LODs could Cd, Hg, primarily result being able introduce ten-fold more concentrated solutions from which bulk had been removed. almost eliminated thus formation spectrally interfering TiO+ completely suppressed. Potentially, combination would allow these determined resorting medium resolution mode, again improving determination by ID-ICP-SFMS.