| Laser ablation allows the direct analysis of solid samples without any sample digestion or very little sample preparation, which facilitates the analysis of refractory solids that do not lend well to dissolution such as coals, graphite and ceramics.;With the sol-gel process, it is possible to obtain amorphous and highly homogenous solids. The objective of the work was thus to investigate whether the sol-gel process can be used to prepare solid pellets from powdered samples that are more suitable for direct analysis by laser ablation than those prepared using more usual pelletization procedures. The use of sol-gels for the preparation of sample pellets leads to a more homogenous dispersion of the analytes in the sample matrix and to more precise measurements by laser ablation.;When the samples to be analyzed are in powdered form, they are generally pressed into pellets prior to laser ablation. However, in order to obtain analytical results of acceptable accuracy and precision using this technique, the signal is normalised using the internal standardization method. However, for an efficient signal normalisation, the internal standard must be distributed in a sufficiently homogenous way in the pellets. |
