Polarographic determination of trace boron in foods

Abstract

A very sensitive polarographic method has been developed for the determination of trace amounts of boron in foods, based on the adsorptive characteristics of the boron complex with beryllium (III) (4-((4-diethylamino-2-hydroxypheny)-azo)-5-hydroxy-2,7-naphthalenedisulphonic acid) at the dropping mercury electrode in a solution of potassium hydrogen phthalate (pH 3.7–4.6). The peak height is directly proportional to the concentration of boron over the range 5 × 10 −9 to 5 × 10 −7 g ml −1. The detection limit and the recovery of the method are 1 × 10 −9 g ml −1 and 89–105%, respectively. The method has been applied to determination of trace amounts of boron in foods, with satisfactory results.