Detection and Development on Total Flavonoids by the Way of Al(NO3)3 Ultraviolet Colorimetry

Flavonoids are mainly distributed in higher plants and almost exist in all green plants of Traditional Chinese Medicine (TCM). In this paper we detect the total flavonoids from the standards and samples arising from special flavonoids frameworks by the way of Al(NO3)3 ultraviolet colorimetry so as to analyze the features of wavelength degree and peak strength in the graph of ultraviolet spectrum. The diverse positions and strengths of absorption band 200-600nm in the ultraviolet spectrum are distinct taking the rutin reference and total flavonoids from Corydalis conspersafor instance. We can find there are 4 pairs peaks & peak valleies (325 and 335; 345 and 355; 360 and 365; 375 and 380) between 300nm and 400nm through scanning the rutin standard solution. There is one strong peak at the 242nm and one weak peak at about 510nm. The important result is that the absorbance always is highest at the 345nm and the absorbance is from 0.133 to 1.487.After that, we put forward some thoughts for the further researches for the verification of chemical and biochemical reaction mechanism by the Al(NO3)3 ultraviolet colorimetry, which can be used for the assay of flavonoids with special structures from the diverse families.