Green synthesis of N-doped carbon quantum dots derived from Ginkgo biloba L. leaves for the determination of butocarboxim based on a turn-off fluorescent probe

Carbon quantum dots (CDs) would gradually replace metal-based quantum dots due to their advantages of excellent photo-physical properties, low toxicity, and outstanding water solubility. In the current study, the hydrothermal synthesis method was simple, convenient, and fast, and herein was used to prepare nitrogen-doping carbon dots (N-CDs) from the combination of Ginkgo biloba L. leaves and ethylenediamine as carbon and nitrogen precursors, respectively. Furthermore, butocarboxim, a carbamate pesticide, can quench the fluorescence of proposed N-CDs. Therefore, the fluorescent signal changes of N-CDs caused by butocarboxim contributed to robust and sensitive butocarboxim sensing. Under the optimal condition, the fluorescent sensor based on the as-prepared N-CDs demonstrated a good linear response for butocarboxim detection in the range of 0.625-40.0 mu g/L with a limit of detection (LOD) of 0.2 mu g/L. In addition, the sensor was successfully applied to butocarboxim determination in real water samples and obtained acceptable results with the recoveries ranging from 97.2 to 106.8% and the RSD less than 6%.

Automated summary

In this study, nitrogen-doping carbon dots (N-CDs) were prepared through hydrothermal synthesis using Ginkgo biloba L. leaves and ethylenediamine as carbon and nitrogen sources, respectively. The fluorescence of the N-CDs was quenched by a carbamate pesticide, which allowed for the development of a sensitive sensor for butocarboxim detection. The sensor showed good performance in real water samples.