Objective: To establish a routine analytical method for the determination of plasma puerarin by LC/LC-UV

and used for the investigation of pharmacokinetics of puerarin. Method: LC1 system column was FRO-XB C18 (4.6 mm×30 mm

20 μm

ANAX)

with mobile phase consisting of 20 mmol ·L-1 ammonium acetate-acetonitrile (75∶25) at the flow rate of 1.0 mL ·min-1. The column temperature was at 40 ℃. LC2 system column was UC-XB C18(4.6 mm×300 mm i.d

5 μm

ANAX)

with mobile phase consisting of 20 mmol ·L-1 ammonium acetate (pH 3.8 adjusted by formic acid)-acetonitrile (86∶314) at the flow rate of 1.2 mL ·min-1. The detection wavelength was at 248 nm. Flow of transferring was 1.0 mL ·min-1

and the windows of ″heart cutting″ was 1.66-2.20 min. The sample loop volume was 200 μL. Result: The linearity range of puerarin was 0.020-4.50 mg ·L-1 (r=0.999 4). The limit of puerarin was 15.0 mg ·L-1.The RSD of intra-day precisions was less than 3% (n=6)

the RSD of inter-day precisions was less than 5% (n=18). The accuracy was 100.3%-102.6%. Conclusion: The method for the determination of puerarin by LC/LC-UV is simple and accurate with high automatization. The method is used for investigation of pharmacokinetics of puerarin.