Study On Fluorescent Properties And Analytical Methods Of Berberine Compounds

Fluorescent properties of10kinds of berberine compounds were studied in this thesis.Relationship between fluorescence and molecular structure was discussed. A TLCfluorescence scanning method for the determination of palmatine, coptisine and epiberberinein Chinese herbal medicine Rhizoma coptidis (Huanglian) was proposed.Three parts are included in the thesis:1. Fluorescent properties of9kinds of berberine compounds were studied. It was foundthat the native fluorescence of berberine compounds were very weak. Addition of surfactant(SDS), β-cyclodextrin, organic solvent (methanol) can enhance the fluorescence. Variation ofpH of the solution had no obvious influence on the fluorescence. In the medium of0.01mol/LSDS, the maximum excitation wavelength λexand emission wavelength λemof berberinebisulfate were350nm and530nm, respectively, fluorescence quantum yield was measured tobe0.0066; the λex/λemof berberine tannate was350/530nm, quantum yield was0.0051; theλex/λemof palmatine hydrochloride was345/530nm, quantum yield was0.0029; the λex/λemofdehydrocorydaline was340/515nm, quantum yield was0.0038; the λex/λemof coptisinehydrochloride was360/545nm, quantum yield was0.016; the λex/λemof worenine was350/528nm, quantum yield was0.014; the λex/λemof epiberberine was360/545nm, quantumyield was0.018; berberrubine and demethyleneberberine had no fluorescence.2. Fluorescent properties of dihydroberberine were studied. It was found thatdihydroberberine had steady fluorescence in acidic aqueous solutions, with λex/λem=360/450nm, quantum yield0.0051. When pH>4.0, dihydroberberine was easily oxidized intoberberine, causing a fluorescence quenching. Addition of methanol into a dihydroberberineaqueous solution led to a decrease in fluorescence intensity.3. Palmatine, coptisine and epiberberine can produce steady fluorescence on silica gelplate. According to this fact, a TLC fluorescence scanning method was proposed for thedetermination of these components in Chinese herbal medicine Rhizoma coptidis (Huanglian),and the results were1.55%,2.46%and1.28%, respectively.