Spectral Properties And Analysis Of Fluorescent Components Of Chinese Medicine Qinpi

Fluorescence spectra of Fraxin and Fraxetin,active components of Chinese herbal medicine Qinpi (Cortex Fraxini), were studied in this thesis. Influence of environment conditions on fluorescence spectra of Aesculin and Aesculetin were investigated. A new thin-layer fluorescence scanning method was proposed for determination of Aesculin and Fraxin in Qinpi, and the feasibility of the new method was tested by high performance liquid chromatography (HPLC).Five parts were included in this thesis:1. Fluorescence spectrum of Fraxin was reported for the first time, and influences of experimental conditions on fluorescence spectra were also studied. Using quinine bisulfate as a reference, fluorescence quantum yields of Fraxetin aquious solution with pH 9.42 were measured to be 0.58 at excitation wavelength 387 nm.2. The intrinsic and sensitized fluorescence spectra of Fraxetin were reported for the first time, and influences of environmental factors on its fluorescence were investigated. The fluorescence of Fraxetin was very weak, its fluorescence quantum yields was 0.016. We found that fluorescence of Fraxetin can be sensitized by borax. Fluorescence quantum yield of Fraxetin-borax complex was measured to be 0.077.3. Influence of environment conditions on fluorescence spectra of Aesculin and Aesculetin were investigated. It was found that borax and aluminium ion can markedly sensitize the fluorescence of Aesculetin.4. Using a method of column chromatography, fluorescent components of Qinpi were separated from a drug sample, and two fluorescent compounds were obtained. By thin-layer chromatographic contrast with standars and study of spectral properties, the two compounds were proved to be Aesculetin and Aesculin, respectively.5. Based on the fluorescence properties of Fraxin and Aesculin, a new thin-layer fluorescence scanning method was proposed for their analysis, and its feasibility was tested by a HPLC method.