Objective: The aim of this study was to develop an HPLC method with programmed UV detection wavelength for the simultaneous determination of shanzhiside methyl ester

8-O-acetyl shanzhiside methyl ester and 2'

4'-dihydroxy chalcone in Qizheng Xiaotong plaster. Method: The samples were separated on a Syncronis C18 Dim.(mm) column(4. 6 mm×250 mm

5 μm)by a linear gradient elution(0-12 min

11% A; 12-17 min

11%-18% A; 17-25 min

18% A; 25-40 min

60% A)using acetonitrile (A) and 0.05% [phosphoric acid solution] (B) as mobile phase at a flow rate of 1.0 mL·min-1 and the eluate was detected by programmed wavelength (0-24 min

235 nm for shanzhiside methyl ester

8-O-acetyl shanzhiside methyl ester;24.01-50 min

365 nm for 2'

4'-dihydroxy chalcone ). Result: Shanzhiside methyl ester

8-O-acetyl shanzhiside methyl ester and 2'

4'-dihydroxy chalcone were well separated excellentlyin less than 48 min within the linear range of 15.12-90.72 mg(r=0.999 9)

15.90-95.40 mg(r=0.999 9) and 4.50-27.00 mg (r=0.999 9)

respectively. The average recoveries of the compounds listed above were 97.12%

104.90%

and 105.63%

respectively. Conclusion: Verys Satisfactory and reproducible results arewere obtained for the simultaneous determination of the 3 active compounds in Qizheng Xiaotong plaster.