Spectral Properties And Fluorimetric Analysis Of Active Components Of Chinese Medicine Eugenia Caryophyllata And Gastrodia Elata

Fluorescence spectra of Traditional Chinese medicine—Eugenia caryophyllata Thunb. (ECT) and Gastrodia elata Bl.(GEB) as well as their marker components eugenol and gastrodin were studied.Influences of experimental conditions on the fluorescence spectra were investigated.New methods for quantitative determination of eugenol and gastrodin in traditional Chinese medicine were proposed based on their fluorescent properties.These methods were simple,reliable and can be used for the quality evaluation of ECT and GEB.Three parts were included in this thesis:1.Fluorescence spectra of eugenol and methyl eugenol were investigated.Influences of acidity and content of alcohol on the fluorescence spectra were studied.It was found that the three-dimensional fluorescence spectrum of eugenol was almost the same as that of methyl eugenol,but there was a discrepancy in strong alkaline condition.Using L-tryptophan as a reference,the fluorescence quantum yields of eugenol were measured to be 0.08 in aqueous solution containing 10%ethyl alcohol,and 0.17 in absolute ethyl alcohol;the fluorescence quantum yields of methyl eugenol were 0.14 in aqueous solution containing 10%ethyl alcohol,and 0.20 in absolute ethyl alcohol.2.Fluorescence spectrum of the ethanol extract of ECT was investigated.Two methods for the determination of eugenol in ECT were proposed based on the fluorescence properties of eugenol.The content of eugenol in an ECT sample was deternined to be 11.44%by using a fluorescence method without pre-separation.The detection limit DL of the method was 0.0160μg ml^-1.Another method was proposed based on thin-layer fluorescence scanning, using petroleum ether(60-90℃)-ethyl acetate(9:1) as mobile phase,and the result of the determination was 11.50%.3.Fluorescence spectra of GEB and its marker component gastrodin were investigated. Influences of acidity,metal irons,borax,surface active agent(SDS and HTAB) on the fluorescence spectra were studied.It was found that there were other components in GEB, which having similar fluorescent properties with gastrodin.Using L-tryptophan as a reference, fluorescence quantum yield of gastrodin was measured to be 0.12 at excitation wavelength 270 nm.The content of gastrodin in a Gastrodin Capsules sample was detected by a fluorescence method.Using a new thin-layer fluorescence scanning method proposed in this work,the content of gastrodin in a GEB sample was determined to be 0.419%.The reliability of the new method was examined by a HPLC/fluorescence detection method,and the result was 0.445%.