Fluorescent Properties And Analysis Of Scoparone And 7-methoxy Coumarin In Chinese Herbal Medicines

Fluorescence spectra of scoprone and 7-methoxy coumain, active components of Chinese herbal medicine, were studied in this thesis. Thin-layer fluorescence scanning methods for determination of scoprone in Chinese olive (Qingguo) and Sweet wormwood (Qinghao) and 7-methoxy coumain in Herba artemisiae scopariae (Yinchen) were established. Three-dimensional fluorescence control spectra of Qinghao and Yinchen were proposed, which can be used in crude drugs identification.Two parts were included in this thesis:1. Fluorescence spectra and fluorescence quantum yield of scoparone have been studied. It was found that scoparone aqueous solutions have strong and steady fluorescence in the range of pH 2.0～8.7, with maximum emission wavelength at 432 nm and excitation wavelengths at 344, 290 and 230 nm. In neutral conditions, an excellent linear relationship between fluorescence intensity and concentration was observed. Using quinine sulfate as a reference, fluorescence quantum yield of scoparone at maximum excitation wavelength 344 nm was measured to be 0.52. A thin-layer fluorescence scanning methods for determination of scoprone in Chinese herbal medicine was established, and the contents of scoparone in Qingguo and in Qinghao were determined to be 0.00152% and 0.00113%, respectively. Thin-layer fluorescence scanning chromatogram and 3D fluorescence fingerprint spectra of some crud drugs containing scoparone were studied for identification of these drugs.2. Fluorescence spectra and fluorescence quantum yield of 7-methoxy coumain have been studied. It was found that 7-methoxy coumain aqueous solutions have strong and steady fluorescence in the range of pH 2.0～8.1, with maximum excitation wavelengths at 325 nm and emission wavelength at 392 nm. In neutral conditions, an excellent linear relationship between fluorescence intensity and concentration was observed. Using quinine sulfate as a reference, fluorescence quantum yield of 7-methoxy coumain at maximum excitation wavelength 325 nm was measured to be 0.44. A thin-layer fluorescence scanning methods for determination of 7-methoxy coumain in Yinchen was established, and the content of 7-methoxy coumain in a Yinchen sample was determined to be 0.0274%. Moreover, 3D fluorescence control spectra of Yinchen were proposed , which can be used in Yinchen crude drugs identification.