AChE biosensor based on aniline-MWNTs modified electrode for the detection of pesticides

Based on the change in electrochemical behavior of enzymatic activity induced by organophosphates (OP) compounds, a simple electrochemical method has been developed for investigation of Organophosphates (OP) compounds using acetylcholinesterase (AChE) biosensor. Aniline (AN) and multiwall carbon nanotubes (MWNTs) are modified on the surfuce of glassy carbon electrode(GCE). The electrochemical behavior of AChE-AN-MWNTs/GCE was studied, and the results showed the AN-MWNTs promoted electron-transfer reactions at a lower potential and catalyzed the electro-oxidation of thiocholine, thus increasing detection sensitivity. Using dichlorvos as a model pesticide, the biosensor had good linearity in the concentration range of 50ngL^-1-1μgL^-1 and 50μgL^-1-5mgL^-1 with a correlation coefficient of 0.9995 and 0.9990, respectively. The detection limit was 10ngL^-1. The biosensor exhibited high sensitivity, good reproducibility and stability, and it was suitable for trace detection of OP pesticide residue.