Indirect voltammetric determination of trace hydroxylamine using magnetic microspheres

A new indirect voltammetric method for the determination of hydroxylamine is described. It is based on the reduction of an electroactive derivative of hydroxylamine on the surface of a magnetic electrode. The electroactive derivative produced by hydroxylamine reacted with magnetic polymer microspheres containing carbonyl groups on the surface. The experimental conditions are discussed. It was found that the peak potential (Ep) of the derivative was -0.46 V (vs. Ag/AgCl) under optimum conditions. Hydroxylamine could be determined in the range of 5-2,000 microg l(-1) with the detection limit of 2 microg l(-1) and relative standard deviation for the determination of 100 microg l(-1) hydroxylamine was 2.35%. Satisfactory results were obtained for the determination of hydroxylamine in aqueous medium.