[The common and variation peak ratio dual index sequence analysis on UV fingerprint spectra of Paeonia Lactiflora Pall].

Baishao and Chishao (Paeonia Lactiflora Pall.) and their close relative Danpi (Paeonia Suffruticosa Andr) samples were estimated quantitatively, based on their UV fingerprint spectra of the extracts obtained with chloroform, ethanol and water, by applying the common and variation peak ratio dual index sequence analysis method. The analytical results showed that the Baishao samples B2, B3 and B4 from the closest regions were the most similar samples. Their common peak ratios were larger than 70 percent and their variation peak ratios were less than 33.3 percent. However, there existed obvious differences among Baishao sample group 1 (B1 and B5), group 2 (B2, B3 and B4) and group 3 (B6) from different regions. The common peak ratios among group 1 (B1 and B5) and group 2(B2, B3 and B4) were lower than 60 percent, while those among group 1 (B1 and B5) and group 3 (B6) were less than 57 percent. The Baishao samples B1 and B5 from the same region collected in different years were of significant disparity, their common peak ratio was only 44.4 percent, but their variation peak ratios were larger than 100 percent. In fact, this method reaches the limitation of quantitative identification of herbs, and can distinguish at least two samples quantitatively.