Electrochemical sensor for imidacloprid detection based on graphene oxide/gold nano/β-cyclodextrin multiple amplification strategy

• GO/Au NPs/β-CD modified electrode base-electrochemical sensor for imidacloprid determination reported for the first time. • Multiple amplification strategy enhanced sensitivity. • Excellent range of response, limit of detection, repeatability, and selectivity. The key to improving the sensitivity of electrochemical sensors for direct detection is the introduction of catalytically amplified nanomaterials. Accordingly, in this study, a new strategy for the preparation of electrochemical sensors with multiple amplification effects is proposed. Graphene oxide (GO), gold nanoparticles (Au NPs), and β-cyclodextrin (β-CD) were introduced to the surface of a glassy carbon electrode via cyclic voltammetry to prepare a modified electrode sensor with a GO/Au NPs/β-CD thin film. The prepared sensor effectively catalyzed and amplified the reduction current of imidacloprid in a B-R buffer with pH=5.0 owning to the multiple amplification effects of GO/Au NPs/β-CD. A good linear relationship was observed the level of the reduction current response and the imidacloprid at concentrations ranging from approximately 5×10 −10 to 3000×10 −10 mol L −1 ; thus, a new imidacloprid detection method using an electrochemical sensor was established. The new method, whose detection limit reached 1.33×10 −10 mol L −1 , was tested on actual samples, achieving recoveries of 92.0% to 110.0%.