Differential Pulse Voltammetric Determination of Traces of Hydrazine Using Magnetic Microspheres

 A new type of magnetic polymer microspheres containing aldehyde groups at the surface was synthesized. It can react with hydrazine to produce an electroactive adduct. Reduction of this derivative, which was adhering to the magnetic electrode is possible and shown to be effective in an indirect determination of hydrazine. The electrode structure and the experimental conditions were discussed. Under optimum conditions, it was found that the peak potential (Ep) of the derivative of hydrazine is −1.04 V (vs. Ag/AgCl). Hydrazine can be determined in the concentration range 1–800 µg l−1. The detection limit for hydrazine is 0.5 µg l−1. The relative standard deviation for determinations of 100 µg l−1 of hydrazine is 2.51%. The method could be applied to the determination of hydrazine in water samples at the 10–500 µg l−1 level with satisfactory recovery.