Sample Pretreatment for Trace Speciation Analysis

Speciation analysis is already a challenge, and speciation analysis at trace levels is even more difficult. However, even the results obtained with the most reliable methods and procedures mean nothing if the sample does not represent the investigated object or the speciation has changed during the sampling step. Any chemical (pH, oxygenation, UV exposition) or physical changes (drying, fragmentation) have an influence on the speciation. For this reason all steps of analytical procedures (sampling, transport, storage, conservation), especially in case of procedures meant for trace speciation analysis, have to be very carefully studied for potential changes they may cause in sample’s properties. It seems impossible that the speciation does not change during these critical stages of every trace analysis, but we have to strive for perfection and create procedures that would prevent the changes as much as possible. The publication is about: Sampling and sample transport; Selection of vessels ; Contamination of the sample with various substances; Elimination of UV-Vis irradiation ; Oxidation and desorption of carbon dioxide; Temperature lowering just after sampling; Suspended matter separation – fractionation in water; Chemical modification of the sample; Dehydration of samples and others aspects.