[Simultaneous determination of four acids active compounds in Erodium stephanianum by RP-HPLC].

To establish a RP-HPLC method for the determination of four acids compounds including gallic acid, protocatechuic acid, corilagin and ellagic acid in Erodium Stephanianum. The RP-HPLC separation was performed on an Agilent TC-C18 analytical column (4.6 mm x 250 mm, 5 microm). The mobile phase was methanol (A) -water containing 0.4% H3PO4 (B) with gradient elution mode at the flow rate of 0.8 mL x min(-1). The detection wavelength was set at 259 nm, and the column temperature was 30 degrees C. The liner ranges of gallic acid, protocatechuic acid, corilagin and ellagic acid were 0.059-2.360 g x L(-1) (r = 0.999 6), 0.017-0.672 g x L(-1) (r = 0.999 9), 0.351-14.040 g x L(-1) (r = 0.999 9), and 0.151-6.040 g x L(-1) (r = 0.999 8), respectively. The average recoveries (n = 3) were 99.45% (RSD 1.5%), 98.65% (RSD 1.7%), 100.3% (RSD 2.0%), and 98.90% (RSD 1.2%), respectively. The method is simple and accurate with a good reproducibility and can be used for quality control of Erodium stephanianum.