Chemical correlation between Gegen Qinlian dispensing granule and its four raw herbs by LC fingerprint

Gegen Qinlian dispensing granule, a favorite composite formula, is a combination of Radix Puerariae Lobatae, Radix Scutellariae, Rhizoma Coptidis and Radix et Rhizoma Glycyrrhizae Praeparata cum Melle. To develop a method to overall evaluate correlation between the formula and its four raw herbs, LC fingerprints of the formula and its raw herbs were developed and LC-DAD-MS was employed to identify the components in the formula fingerprint. According to the characteristic fragmentation behavior of known flavonoids, alkaloids and saponins isolated from the four raw herbs as well as retention time, UV and MS data of detected compounds, a total of 23 constituents in the formula fingerprint were structurally characterized. Chemical correlation between the formula and the four crude herbs was evaluated qualitatively and quantitatively by the developed LC fingerprints. The results showed that 8 components in the formula fingerprint were addressed to Radix Puerariae Lobatae, 11 to Radix Scutellariae, 7 to Rhizoma Coptidis, 3 to Radix et Rhizoma Glycyrrhizae Praeparata cum Melle, and that the relative area ratios of the common peaks in the formula vary slightly in comparison with corresponding ratios in its crude herbs, demonstrating the chemical constituents in the formula have patterns similar to those in its crude herbs.