Objective: To establish a method for the determination of rosmarinic acid in rat plasma after iv Danhong Zhusheye. Method: Male SD rats six

after iv Danhong Zhusheye (10 mL ·kg-1)

Separately at differ ent times take blood

with cinnamic acid as internal standard

Liquid-liquid extraction processing

determination of rosmarinic acid by HPLC

Diamonsil C18 colurme was used. Acetonitrile-0.4% phosphoric acid solution as mobile phase

gradient elution

at the flow rate of 1 min ·mL-1 with detection wave length at 286 nm. Result: Rosmarinic acid had good linear relationship when its concentration was between 4.0-100.0 g ·L-1. Recoveries were between 85.0%-101.4%. The intra-day and inter-day precision of this method were 4.00%-6.76% and 4.50%-7.81%

respectively. Concentration of rosmarinic acid in rat plasma at different times Separately were 85.44

75.09 g ·mL-1

61.13

54.73

43.02

20.92

10.12

7.18

4.28 mg ·L-1. Conclusion: The method is simple

quick and convenient for the determination of rosmarinic acid.