荧光分光光度法测定大山楂丸中黄酮类化合物的含量

设定荧光激发/发射波长为281/352 nm,激发和发射光狭缝宽度为5 nm,在300~500 nm波长范围内测定荧光光谱。对酸度、表面活性剂、温度、反应时间及铝离子浓度等影响因素进行考察,优化试验条件。结果：在盐酸酸性介质中、无表面活性剂、常温下、反应时间30 min、铝离子浓度为2×10-4mol/L时,体系的荧光强度最大且稳定。当槲皮素的浓度范围在0.2×10-5~1.5×10-5mol/L之间时,荧光强度（F）和槲皮素浓度（c）呈良好的线性关系;检测限为2.4×10-8mol/L。3批大山楂丸中总黄酮的平均含量分别为24.56、27.85、25.13 mg/g,与《中国药典》方法测定结果基本一致。结论：本方法操作简便、快速、准确,可用于测定大山楂丸中总黄酮的含量。

Determination of Total Flavonoids in Crataegi Bolus by Spectrofluorimetry

OBJECTIVE：To determine the content of total flavonoids in Crataegi Bolus by spectrofluorimetry. METHODS：The content of the total flavonoids in Crataegi Bolus was determined by spectrofluorimetry with quercetin as reference substance with wavelength of fluorescence excitation/emission of 281/352 nm,slit width of excitation/emission of 5 nm and the fluorescence spectra of 300-500 nm. The influential factors such as acidity,surfactant,temperature,reaction time and the concentration of aluminum ion were investigated to optimize the experimental conditions. RESULTS：The maximum and stable fluorescence intensity was obtained in acid medium of hydrochloric acid in the absence of surfactant under room temperature with reaction time of 30 min and aluminum ion concentration of 2×10-4mol/L. Fluorescence intensity（F）and the quercetin concentration（c）were in good linear relationship when the concentration of quercetin was between 0.2×10-5and 1.5×10-5mol/L. The detection limit of this method was2.4×10-8mol/L. The average contents of the total flavonoids in three batches of Crataegi Bolus were 25.45 mg/g,27.85 mg/g and25.13 mg/g,respectively,which were basically in conformity with those determined by the method specified in China Phamacopoeia. CONCLUSIONS：The method is simple,rapid and accurate and thus it is applicable for determination of the total flavonoids in Crataegi Bolus.