The present invention relates to the field of analytical chemistry, especially the preparation of the sample before the assay. This is applied to cases where it is necessary to obtain a substance from the sample matrix, or when it is appropriate prior to the determination of a substance pre-concentrate the analyte by an extraction procedure.
Using automated flow analytical technique based on a closed system, in which two units are connected - one part is based on a conventional system, sequential injection analysis, and the second is designed for handling with extraction mixture for determination of a substance after automatic extraction into immiscible solvent.