Abstract: Fluorescent carbon quantum dots(CDs)were prepared from edible prickly ash by pyrolysis method and CDs was further modified β-CD. The optical properties and macroscopic features of CDs were respectively characterized by fluorescence spectroscopy and transmission electron microscopey(TEM). The results showed that the wavelength of fluorescence excitation and emission were at 315 nm and 429 nm, respectively. The fluorescence quantum yield was 0.60 and the average diameter of the carbon dots was 4.2 nm. Owing to acetylcholine bromide can sensitize the fluorescence of carbon quantum dots, it can be used for the analysis and detection of acetylcholine bromide in milk. With the pH7.0 and the temperature is 25 ℃, the fluorescence intensity is proportional to the amount of acetylcholine bromide, the linear regression equation is ΔF=314.72c+134.54, the linear range is from 0.08 to 1.6 μmol/L, r=0.997 9, the standard deviation is 1.75, and the detection limit is 1.62×10^-8mol/L. This method was used to detect the acetylcholine content in milk and yogurt, and the recovery rate is between 98% and 102%.

Key words: the prickly ash, carbon quantum dots, fluorescence sensitization, acetylcholine bromide