Highly sensitive spectrofluorimetric determination of trace amounts of scandium with salicylaldehyde salicyloylhydrazone

Abstract

The fluorescent reaction of salicylaldehyde salicyloylhydrazone (SASH) with scandium was studied in detail. Based on this chelation reaction, a highly sensitive spectrofluorimetric method was developed for the determination of scandium in ethanol–water (1 + 1 v/v) medium at pH 5.0. Under these conditions, the Sc–SASH complex had excitation and emission maxima at 388 and 465 nm, respectively. The linear range of this method was 0.40–100 ppb and the detection limit was 0.12 ppb of scandium when a standard additions method was used in the assay. The molar ratio of scandium to the reagent was found to be 1:1. The effect of interferences was studied. The proposed method was successfully used to determine trace amounts of scandium in geological soil samples. Extraction with 1-phenyl-3-methyl-4-benzoylpyrazolone– benzene from formic acid–sodium formate medium (pH 3) was used to separate Sc from interfering elements in the soil samples.