Elemental digestion before analysis

The practice of multi-elemental analysis has become essential and commonplace in many fields. In the geosciences, the chemical industry, the oil industry or the automotive industry, the elemental composition of the materials processed can modify their physico-chemical properties. Preparing samples for analysis therefore requires a number of factors to be taken into account. Firstly, the elements of interest need to be listed with their expected abundances, since in some fields, such as petroleum-derived products, major, minor and trace elements, and even ultratraces, can be of interest in geosciences. Other factors such as the sample masses available (from milligrams to hundreds of grams) and the types of matrices to be dissolved, such as organic matrices (fats, oils, etc.), silicate matrices or even biological matrices (tissues, biological fluids, etc.) will impact on the choice of preparation techniques.

These sample processing techniques have been mastered since the 1980s, but recent developments in analytical instrumentation have led us to reflect on other solution techniques: as analyzers such as mass spectrometers (ICPMS, TIMS), adsorption spectrometers (SAA) or emission spectrometers (ICP OES) become increasingly sensitive, these methods need to be both "cleaner" and extract increasingly infinitesimal quantities of material.

Solution treatment is used to mineralize samples for analysis, freeing inorganic molecules from organic ones. It can be carried out wet (with reagents and solvents) or dry (calcination).

Only the dissolving of solid samples is covered in this article.