Reduction behavior of fenoxaprop-p-ethyl and its voltammetric determination

Abstract

The reduction behavior of fenoxaprop-p-ethyl (FNX) was studied on a hanging mercury drop electrode. FNX showed 2 reduction peaks at about -0.7 V and at about -0.9 V versus Ag/AgCl/3.0 M KCl in Britton-Robinson buffer at pH 4.8. Both reductions were irreversible and adsorption was effective. The reduction peaks were assigned to the reduction of C=N to CH-NH and the reduction of C=O to CH-OH. Square-wave voltammetry has been proposed and validated for quantification of FNX in different samples. The linear working range was established as 0.30-15.0 mu M. Limit of detection and limit of quantification were calculated as 0.07 mu M and 0.24 mu M, respectively. The proposed method was successfully applied for the determination of FNX in tap water, river water, and plant samples with recoveries between 95.7% and 99.6% showing a relative standard deviation of less than 15%.