Sample preparation steps for analysis by atomic spectroscopy methods: Present status

Analysis by spectroscopic methods practically always necessitates a simple or more complex preparation of the sample. These steps are generally the most critical part of analysis because they are responsible for the most important errors. This is particuarly true for solid samples which have to be generally brought in a solution in order to satisfy needs of introduction systems of main spectroscopic methods usually utilized in routine laboratories. For several types of samples (e.g. animal tissues, metals and alloys...) the solubilization process is not very problematic. For other samples, generally with silica in the matrix (e.g. soils, sediments, plant tissues...), some problems may appear due to volatilization or insolubilization phenomena. In these cases, recoveries are poor and a more appropriate solubilization process has to be considered. Unfortunately, it is not always easy to reach a good decision as a consensus does exist for all types of samples. In this work, we discuss present possibilities which concern the above-mentioned preparation steps.