Study On Fluorescent Propetries And Analytical Methods Of Tetrahydroprotoberberines

Fluorescent properties of tetrahydroprotoberberines compounds (THPB), includingd-corydaline, l-tetrahydropalmatine, d-tetrahydropalmatine, tetrahydrocoptisine andtetrahydroberberine, they are extacted from Chinese herbal medicine Corydalis yanhusuo W.T. Wang (Yanhusuo in Chinese), and l-stepholidine (l-SPD), which is extracted from Chineseherbal medicine Stephania japonica (Qianjinteng in Chinese), were studied. A thin layerchromatography-scanning method and a high performance liquid chromatographic methodcoupled with fluorescence detector for the determination of tetrahydropalmatine (includingl-tetrahydropalmatine and d-tetrahydropalmatine) in Yanhusuo crude drugs were proposed.Two parts are included in this thesis:1. Fluorescence spectra and absorption spectra of the THPB compounds were studied.Influences of experimental conditions (pH, ionic strength, and solvent) on spectral propertywere tested. Using L-tryptophan as a reference, fluorescence quantum yields of the THPBcompounds were measured. L-stepholidine has strong fluorescence intensity in the conditionof pH=2.0~3.0, while other compounds have strong fluorescence intensity in conditions ofpH=2.0~5.0. The maxmum excitation wavelength (λex) and emission wavelength (λem) ofd-corydaline are282nm and312nm, respectively, its fluorescence quantum yield is0.206.The λexand λemof L-tetrahydropalmatime are281nm and314nm, quantum yield is0.193. Theλexand λemof D-tetrahydropalmatine are282nm and312nm, quantum yield is0.116. The λexand λemof tetrahydroberberine are284nm and326nm, quantum yield is0.224. The λexandλemof L-stepholidine are281nm and312nm, quantum yield is0.059. The λexand λemoftetrahydrocoptisine are288nm and326nm, quantum yield is0.247.2. Three dimensional (3D) fluorescence spectra of Yanhusuo crude drugs andtetrahydropalmatine were studied. It was found that there are several fluorescent componentsin Yanhusuo, and their fluorescence spectra are overlapped each other. Therefore, the contentof tetrahydropalmatine in Yanhusuo crude drugs cannot be determined directly withoutpre-seperation. A thin layer chromatography-fluorescence scanning method and a thin layerchromatography-absorption scanning method were studied for the determination oftetrahydropalmatine in Yanhusuo crude drugs, the results were0.0234%and0.0168%,respectively. A high performance liquid chromatographic method coupled with fluorescencedetector for the determination of tetrahydropalmatine in Yanhusuo crude drugs was alsoproposed, the result was0.0299%.