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

Abstract

The electro-oxidation of zearalanone (ZEA) adsorbed on glassy carbon electrodes in 20% acetonitrile (ACN) + 80% 1 <i>M </i>HClO₄ aqueous solution has been studied for the first time by using cyclic and square wave voltammetry. Experimental results<i> </i>clearly demonstrate the surface nature of the electrochemical reaction. The optimum accumulation potential (<i>E</i>_acc)<i> </i>and

optimum accumulation time (<i>t</i>_acc) 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>I</i>_p,n) <i>versus c</i>*_ZEA in the concentration range from 2×10^-7- 1.5 ×10^-5 <i>M </i>with a detection limit of 2×10^-7 <i>M </i>at a signal to noise ratio of 2: 1.<br> Cyclic and square wave voltammograms show an EC_irrev mechanism to be the most probable mechanism to describe the surface electrochemical reaction. The dependence between <i>_I</i> _p,n and <i>E</i>_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.