A sensitive fluorescent sensor for selective determination of dichlorvos based on the recovered fluorescence of carbon dots-Cu(II) system

In this paper, a simple and sensitive fluorescent sensor for dichlorvos was first constructed based on carbon dots-Cu(II) system. These carbon dots were obtained by simple hydrothermal reaction of feather. The fluorescence of these carbon dots can be selectively quenched by Cu2+ ion. When acetylcholinesterase and acetylthiocholine were introduced into the system, thiocholine came into being, which can react with Cu2+ ion and restore the fluorescence of the system. The reaction mechanism between Cu2+ ion and thiocholine was confirmed by X-ray photoelectron spectroscopy. As one kind of acetylcholinesterase inhibitor, organophosphorus pesticides can be detected based on this sensing system. As an example of organophosphorus pesticides, dichlorvos was detected with a linear range of 6.0 × 10−9-6.0 × 10−8 M. This sensing system has been successfully used for the analysis of cabbage and fruit juice samples.