Representative sampling using single-pulse laser ablation with inductivelycoupled plasma mass spectrometry

Single pulse laser ablation sampling with inductively coupled plasma mass s pectrometry (ICP-MS) was assessed for accurate chemical analysis. Elemental fractionation (e.g. Pb/U), the quantity of ablated mass (crater volume), I CP-MS intensity and the particle contribution (spike signal) during single pulse ablation of NIST 610 glass were investigated. Pb/U fractionation sign ificantly changed between the first and second laser pulse and showed stron g irradiance dependence. The Pb/U ratio obtained by the first pulse was usu ally higher than that of the second pulse, with the average value close to the representative level. Segregation during laser ablation is proposed to explain the composition change between the first and second pulse. Crater v olume measurements showed that the second pulse produced significantly more ablated mass. A roll-off of the crater depth occurred at similar to 750 GW cm(-2). The absolute ICP-MS intensity from the second pulse showed no corr elation with crater depth. Particle induced spikes on the transit signal sh owed irradiance and elemental species dependence.