Simultaneous determination of 12 index components and compatibility changes in Longchai decoction by liquid chromatography-mass spectrometry.

The aim of this study was to explore the traditional decoction theory of Chinese medicine compound prescriptions. To control the quality of Longchai decoction and to analyze the changes of chemical components before and after compatibility, the determination method of 12 index components including salidroside, wogonoside, liquiritin, isoliquiritin, liquiritigenin, quercetin, isoliquiritigenin, isorhamnetin, wogonin, saikosaponin A, saikosaponin D and ursolic acid by liquid chromatography-mass spectrometry (LC-MS) was established. The 12 index components were detected by LC-MS with the Agilent Zorbax SB C18 (3.1 x 100 mm, 3.6 mu m) column, the mobile phase consisted of acetonitrile-0.1% methanoic acid with gradient elution at the flow rate of 0.25 mL min(-1) and the column temperature was maintained at 30 degrees C. All the samples were isolated to baseline. All calibration curves showed good linear regression (r(2) > 0.9978). The average recoveries were between 99.16 and 103.25% of relative standard deviation <2.82% (n = 5). Obtained results indicated that the content of index components was increased in traditional decoction, compared with mixed individual decoctions. This method with good resolution and high precision could be used for the quality control of Longchai decoction.