[Determination of catalpol in dried rehmannia root and Taohong Siwu Decoction with high performance liquid chromatography].

ABSTRACT

OBJECTIVE: To determinate the catalpol contents in dried rehmannia root and Taohong Siwu Decoction containing rehmannia root with high performance liquid chromatography (HPLC). METHODS: Catalpol was separated on a YWG-C18 column using water-acetonitrile (99.40.6) as mobile phase and detective wavelength at 210 nm. RESULTS: The linear curve of tested catalpol concentration within the range of 0.0536-5.3600 microg/microl was ideal (n=5, r=0.999 7). The average recovery rate of the dried rehmannia root and Taohong Siwu decoction was 98.7% (RSD=0.48%) and 98.2% (RSD=1.29%) respectively. CONCLUSION: HPLC method is accurate and valuable for the quality control of Radix Rehmanniae and Taohong Siwu Decoction.