Determination of loganin and paeoniflorin in enriched Liuwei Dihuang pills with HPLC

Objective To establis h a determination method of loganin and paeoniflorin for Liuwei Dihuang pill.Method There were the stationary phase with Hypersil C18(200 mm× 4.6 mm 5 μm) Nova-PakC18 Guard-PakTM,0.05% phosphoric acid solution(A)-acetonirtile(B),The photodiode array detector at 233nm,column temperature 30℃ and the flow rate 1 mL/min in HPLC.Result For loganin,the calibration curve was linear over the range of 0.11～1.10 μg(r= 0.999 5),the average recovery of the method was 100.1%,RSD=3.0%(n=5).For paeoniflorin,the calibration curve was linear over the range of 0.15～1.50 μg(r=0.999 2),the average recovery of the method was 100.7%,RSD=2.1%(n=5).Conclusion The method is reliable and accurate,which can be used to determine the contents of loganin and paeoniflorin in Enriched Liuwei Dihuang pills.