Fluorescence Reaction System of Quercetin,Gallium(Ⅲ) and Sodium Lauryl Sulfonate and Its Application to the Determination of Flavones in Sophorin,Folium Ginkgo Biloba and Dried Tangerine

In a slightly acidic solution of HCl and in the presence of sodium lauryl sulfonate,a yellow fluorescent complex was formed between Ga(Ⅲ) and quercetin with mole ratio of 1 to 1.Excitation wavelength (λex) and emission wavelength (λem) were found to be 435.4 nm and 485.6 nm respectively.Linear relationship between fluorescence intensity and concentration of quercetin was obtained in the range of 4.0×10-7-3.1×10-6mol·L-1 with detection limit of 1.8×10-10mol·L-1.The proposed method,was used in the analysis of some traditional Chinese medicine,giving values of RSD′s (n=8) and recovery in the ranges of 0.23%-0.64% and 90.1%-101.3%.