Quality evaluation of Carthami Flos by HPLC-UV

A HPLC-DAD method was developed for simultaneous determination of four marker compounds, kaempferol-3-O-rutinoside, safflomin A, safflomin B and bidenoside C, in the extract of the flowers of Carthamus tinctorius Linne. Natural samples were extracted in 50% aqueous methanol by ultra-sonication for 60 min. Marker compounds were separated on a C18 column by two-step gradient elution of mobile phase (acetonitrile/water) at a flow rate of 0.75 mL/min and detected at 210 nm. The retention times of safflomin A and safflomin B were shifted according to the pH of the mobile phase. The optimized analytical method was validated to confirm linearity, precision, accuracy and stability of marker compounds. The method was successfully employed to analyze 17 natural samples from different regions, and the data matrix was monitored and visualized by principal component analysis. The assay method could be applied for quality control of the flowers of C. tinctorius Linne.