An Electrochemical Method for the Determination of Trace Mercury (II) by Formation of Complexes With Indigo Carmine Food Dye and Its Analytical Application

摘要

The interaction between mercury and indigo carmine (IC) was studied using differential pulsevoltammetry (DPV) technique. In aqueous medium, a decrease of oxidation current of IC wasobserved due to the formation of a complex of IC with Hg (II). The reaction of complexation wasmonitored and some important parameters such as metal concentration, pH, temperature and time ofreaction were investigated and optimized. Under the optimum conditions, the linear range of thecalibration curve, obtaining by representing the IC oxidation current as function of the Hg (II)concentration (pH 10), was from 25 nM (5 ppb) to 200 nM (40 ppb) Hg (II) and the detection limit was7.5 nM (1.5 ppb). The results show that this new method enable simple, a sensitive and rapiddetermination of mercury.