Electrochemical behavior and analytical detection of Imidacloprid insecticide on a BDD electrode using square-wave voltammetric method

A sensitive square-wave voltammetric method for the determination of Imidacloprid (IMD) was developed using electrochemically pretreated boron-doped diamond (BDD) electrode. Aqueous solutions were prepared with Confidor 200 SL as the commercial formulation of IMD. Sodium sulfate (Na2SO4) was used as supporting electrolyte. The influence of operating parameters, such as the pH of the medium, frequency, pulse amplitude, scan increment and the concentration of IMD was investigated. An irreversible cathodic peak, corresponding to the reduction of IMD is observed at 1.21 V (vs. SCE) and the electrode reaction was controlled by adsorption. Under optimized conditions, the square-wave reduction peak current was linear over the concentration range of (30-200 mu mol L-1) with a detection and quantification limits of 8.60 mu mol L-1 and 28.67 mu mol L-1, respectively. The results were compared with spectrophotometry and HPLC methods under some conditions and found to be in good agreement. To investigate applicability to real samples, the proposed method was applied to the determination of IMD in plum juice. (C) 2016 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.