Abstract
LA-ICP-MS is one of the most promising techniques for in situ analysis of geological and environmental samples. However, there are some limitations with respect to measurement accuracy, in particular for volatile and siderophile/chalcophile elements, when using non-matrix-matched calibration. We therefore investigated matrix-related effects with a new 200nm femtosecond (fs) laser ablation system (NWRFemto200) using reference materials with different matrices and spot sizes from 10 to 55m. We also performed similar experiments with two nanosecond (ns) lasers, a 193nm excimer (ESI NWR 193) and a 213nm Nd:YAG (NWR UP-213) laser. The ion intensity of the 200nm fs laser ablation was much lower than that of the 213nm Nd:YAG laser, because the ablation rate was a factor of about 30 lower. Our experiments did not show significant matrix dependency with the 200nm fs laser. Therefore, a non-matrix-matched calibration for the multi-element analysis of quite different matrices could be performed. This is demonstrated with analytical results from twenty-two international synthetic silicate glass, geological glass, mineral, phosphate and carbonate reference materials. Calibration was performed with the certified NIST SRM 610 glass, exclusively. Within overall analytical uncertainties, the 200nm fs LA-ICP-MS data agreed with available reference values.