Spectral Properties Of Active Components Of Huanglian And Determination Of Berberine By Cyclodextrin Sensitized Fluorescence

In this thesis, fluorescence spectra of four active components of Chinese herbal medicine Huanglian were studied. Influences of experimental conditions on fluorescence spectra were investigated. Three dimensional fluorescence spectra of Huanglian were analysized. A new method for analysis of berberine (Berb) was proposed based on the sensitized fluorescence produced by an inclusion reaction of Berb withβ-cyclodextrin (β-CD). The new method has been applied successfully to the analysis of Berb in some Chinese herbal medicines.The main contents of the thesis were as follows:1. Spectral properties of Berb, palmatine, jatrorrhizine and tetrahydropalmatine, were studied. Influences of acidity, organic solvent, surface active agent (SDS) andβ-CD on fluorescence spectra were investigated. It was found that the fluorescence property of Berb and palmatine were very similar. But, fluorescence enhancement could only be observed in the reaction ofβ-CD with Berb, not in the reaction ofβ-CD with palmtine. This phenomenon can be used to differentiate between the two of them. Tetrahydropalmatine exhibited strong fluorescence peak at short wavelength, different from Berb and palmtine. Jatrorrhizie produced week fluorescence, and could not be enhanced by adding SDS orβ-CD, so it was also different from Berb and palmtine. The dissociation constant of jatrorrhizie was measured to be pKa=8.16 by an absorption method.2. It was found that three dimensional fluorescence spectra of Huanglian showed three types of fluorescence peaks, and they were assigned to fluorescent components. According to the feature of three dimensional fluorescence spectra, feasibility of determination of Berb in Huanglian byβ-CD sensitized fluorescence was discussed.3. Using the fluorescent reaction ofβ-CD with Berb, new methods for determination of Berb in Chinese herbal medicines were proposed and applied to real samples. (1) A method for determination of Berb in Berberine Hydrochloride Tablet was established, and it was satisfied with precision, accuracy, and detection limit. (2) A method for determination of Berb in Huanglian was established, based on the fact thatβ-CD can only react with Berb, while other isoquinoline alkaloids in Huanglian did not interfere with the fluorescent reaction. The contents of Berb in three Huanglian samples were determined to be 5.4%～7.8%, and the result was verified by a fluorescence scanning thin-layer chromatographic (FSTLC) method. (3) The content of Berb in Huangbai sample was determined to be 1.6%, and it was verified by FSTLC method. (4) The content of Berb in Sankezhen sample was determined to be 2.5%, and it was also verified by FSTLC method.