Simultaneous determination of cryptotanshinone, tanshinone I and tanshinone IIA in traditional Chinese medicinal preparations containing Radix salvia miltiorrhiza by HPLC

Abstract A reversed-phase high performance liquid chromatographic method was established for the simultaneous determination of tanshinones in five kinds of traditional Chinese medicinal preparations (TCMPs) containing Radix salvia miltiorrhiza (Chinese herbal name: Danshen). Tanshinones including cryptotanshinone, tanshinone I and tanshinone IIA were successfully separated on a Diamonsil C 18 column (150 mm × 4.6 mm i.d., 5 μm). The mobile phase was a mixture of methanol, tetrahydrofuran, water and glacial acetic acid (20:35:44:1, v/v/v/v), employing isocratic elution at a flow rate of 1.0 mL/min. Detection was accomplished at 254 nm. The compounds were identified by comparing their retention times and UV spectra in the 200–400 nm range with authentic standards. Regression equations revealed good linear relationship between the peak areas of the constituents and their concentrations (correlation coefficients: 0.9998 for cryptotanshinone, 0.9999 for tanshinone I and 1.0000 for tanshinone IIA). The relative standard deviations ( n  = 6) of retention time and peak area were less than 0.25% and 1.00%, respectively. The recoveries were between 96.2% and 102.5%. The proposed method has been successfully applied to the simultaneous determination of the tanshinones in five kinds of Chinese herbal preparations containing Danshen within 20 min.