Pesticide residues rapid detection in vegetables real samples based on nanomaterial-modified acetylcholinesterase biosensor

In this reported work, an acetylcholinesterase (AChE) biosensor based on chitosan-Prussian blue-multiwall carbon nanotubes-hollow gold nanospheres (Chit-PB-MWNTs-HGNs) film was used for detecting pesticide residues in vegetable samples. Three different kinds of sample extraction methods were investigated, such as the oscillation extraction method, the ultrasonication and the centrifugation extraction method and the ultrasonication and filtration extraction method. By comparison, the ultrasonication and centrifugation extraction method was the most appropriate and efficient for the AChE biosensor. After treatment by ultrasonication and centrifugation extraction, the recoveries of the pesticides from vegetable samples were from 76.8 to 105.9% with relative standard deviation lower than 12.68%. Subsequently, the detection results with the AChE biosensor were compared with the standard gas chromatography method. The results indicated that the proposed sample pretreatment method was applicable to the AChE biosensor for pesticide residues detection in real vegetable samples.