Determination of electrochemical properties of the adsorbed zearalanone mycotoxin by using cyclic and square wave voltammetry

The electro-oxidation of zearalanone (ZEA) adsorbed on glassy carbon electrodes in 20% acetonitrile (ACN) + 80% 1 M HClO 4 aqueous solution has been studied for the first time by using cyclic and square wave voltammetry. Experimental results clearly demonstrate the surface nature of the electrochemical reaction. The optimum accumulation potential (E a c c ) and optimum accumulation time (t a c c ) are 0 V and 2 min, respectively. Quantitative determination of ZEA has been performed by Square Wave Voltammetry. Linear calibration curves have been obtained from the net peak current (I p , n ) versus c* Z E A in the concentration range from 2 x 10 - 7 - 1.5 x 10 - 5 M with a detection limit of 2 x 10 - 7 M at a signal to noise ratio of 2:1. Cyclic and square wave voltammograms show an EC i r r e v mechanism to be the most probable mechanism to describe the surface electrochemical reaction. The dependence between I p , n and E p , n on the logarithm of acid bulk concentration indicates a deprotonation reaction to should be the fast follow-up chemical reaction coupled to the initial electron transfer reaction.