Comparison of ferulic acid content in Radix Angelicae Sinensis, Danggui-Buxue-Tang and Danggui-Sini-Tang.

The aim of the present study was to determine the ferulic acid (FA) content of Radix Angelicae Sinensis (AS), Danggui-Buxue-Tang (DBT) and Danggui-Sini-Tang (DST) using the same ultra performance liquid chromatography system and method. FA was eluted using an Acquity BEH C18 column (100x2.1 mm inner diameter; 1.7 mu m). A mobile phase of methanol and 0.5% acetic acid was used and a flow rate of 0.3 ml/min was selected. The calibration curve exhibited a good linear regression (R-2=0.9997). The inter- and intra-day precision measurements of FA ranged between 0.27 and 3.03% and the recovery ranged between 98.44 and 101.64% with relative standard deviation (RSD) values <= 4.73%. The method was reliable and simple. The results of the chromatographic analyses indicate that the FA contents of the DBT and DST decoctions were increased compared with that of AS due to the presence of other herbs.