RECYCLING NEBULIZATION SYSTEM WITH A DISPOSABLE SPRAY CHAMBER FOR ANALYSIS OF SUBMILLIGRAM SAMPLES OF GEOLOGICAL-MATERIALS USING INDUCTIVELY COUPLED PLASMA MASS-SPECTROMETRY

A recycling nebulization system with a disposable spray chamber was developed and evaluated for inductively coupled plasma mass spectrometry (ICP-MS). With the recycling nebulization system, 0.5 g of sample solution is sufficient for 8 min of data acquisition. The sensitivity of the recycling nebulization system was similar to a conventional Scott spray chamber system. Twenty-six trace elements were determined by ICP-MS using four internal standards (Ge, In, Re and Bi) to correct for matrix effects, instrumental drift and enrichment of the sample solution by evaporation. The ability to analyse mineral separates weighing less than 0.1 mg is demonstrated with detection limits similar to conventional procedures. Analyses of selected geological reference materials: Canada Centre for Energy and Mineral Technology (CANMET) SY-2 Syenite Rock, United States Geological Survey (USGS) reference material BCR-1 and W-1 and Centre de Recherches Petrographiques et Geochimiques (CRPG) reference material BR indicate good limits of detection, good accuracy and precision, a very low memory effect and low consumption of sample solution. Results compare well with data reported using conventional ICP-MS analysis. Analysis of the USGS geological reference material, PCC-1, for 14 rare earth elements, at ultra-trace concentration levels using cation-exchange preconcentration, is demonstrated, with limits of detection for solids of from 0.01 to 1 ng g-1 and relative standard deviations of less than 15%.