ABSTRACT
To establish the online two-dimensional liquid chromatography by using double gradient liquid chromatography system and UV detector, in order to simultaneously determine the content of paeoniflorin, paenol, amygdaloside and cinnamic acid. A pump of the two-dimensional liquid chromatography was adopted as the one-dimensional separation pump. C18 (3.0 mm x 150 mm, 3 microm) was used as the analytical column, with acetonitrile as the organic phase and 0.08% phosphoric acid + 0.08% triethylamine as the aqueous phase for gradient elution at the flow rate of 0.5 mL x min(-1). Another pump of the two-dimensional liquid chromatography was adopted as the two-dimensional separation pump. PAII C18 was used as the analytical column, with acetonitrile as the organic phase and 20 mmol, pH 3.0 monopotassium phosphate as the aqueous phase for gradient elution at the flow rate of 0.8 mL x min(-1). The detection wavelengths were set at 218, 230, 275 nm by using wavelength time-switching program. The linearity range of paeoniflorin, amygdaloside, paeonol and cinnamic acid were 5.55-222 (r = 0.999 7), 6.6-264 (r = 0.999 8), 3.3-132 (r = 0.999 5) and 0.315-12.6 mg x L(-1) (r = 0.999 7), respectively. The average recoveries of the four components were between 96.12% and 103.9%. The experiment proved that this method was so rapid and accurate in determination results that it could be used for evaluating drug quality.