OUP accepted manuscript

A large edible fungus Lactarius hatsudake (Lh) was used as carbon source to produce fluorescent carbon dots (CDs) with high quantum yield and high photostability by one-step hydrothermal method.The structure and optical properties of Lh-CDs were characterized by XRD, XPS, FTIR, and UV-Vis, and the stability of Lh-CDs was studied. The maximum excitation wavelength and emission wavelength of Lh-CDs were 324 and 408 nm, respectively, and the average fluorescence lifetime was 2.29 ns.The linear range is 0∼20 μM (R2=0.9972) with detection limit of 36.9 nM.At the same time, the mechanism of fluorescence quenching was internal filtration effect.It showed that Lh-CDS had good selectivity, high sensitivity, and good anti-interference ability to VB12, which provided a new detection method for VB12.