Simultaneous Determination of Four Lignans in Magnoliae Flos Extract by High Performance Liquid ChromatographyElectrospray Ionization Mass Spectrometry
A high performance liquid chromatography-electrospray ionization mass spectrometry- charged aerosol detection( HPLC-MS-CAD) method was established for the simultaneous quantitative analysis of four Lignans in Magnoliae Flos extract. The components were separated on a YMC-Pack ODS-A column( 250 mm× 4.6 mm,5 μm) by gradient elution with methanol and water as the mobile phase at aflow rate of1.0 m L / min. Then the elution solution was routed into MS equipment at a flow rate of 0.3 m L / min and CAD detector at a flow rate of 0.7 m L / min by a split ratio of 3∶ 7 for the further detection. The column temperature was 25 ℃ and the detection wavelength was 278 nm. A method was developed for the quantitative analysis of muti-components by single maker( QAMS) to determine pinoresinol dimethylether,magnoli,1irioresinol B dimethylethe and epi- magnoli A. Magnoli was selected as internal standard and the relative correction factors( RCF) of the four Lignans were calculated. The contents of the four Lignans in Magnoliae Flos extract were determined by both external standard method and QAMS. The QAMS method was evaluated by comparison of its assay result and that of external standard method. Under the selected chromatographic condition,the limits of detection of pinoresinol dimethylether,magnoli,lirioresinol B dimethylethe and epi-magnoli A were 0.34,0.55,0.50 and 0.58 mg / L,respectively,while the linear range were within 6.8-270 mg / L,11-546 mg / L,2.0-101 mg / L and 2. 3- 116 mg / L. The recoveries( n = 9) were 98. 2%- 99. 5%,and the correlation coefficient were 0. 9995- 0. 9998. No significant differences were found between the quantitative results of external standard method and QAMS method. The developed method is accurate,feasible,and can be used for quality evaluation of Magnoliae Flos.