HPLC-DAD-ELSD simultaneous determination of four triterpenoids in RHIZOMA ALISMATIS.

Objective: An analytical method was developed for simultaneously determining alisol C 23-acetate,alisol A,alisol B,alisol B 23-acetate four triterpenoids in the rhizoma of Alisma orientalis. Method: The assay was performed on a Ultimate XB-C 18 column( 4. 6 mm × 250 mm,5 μm) with the mobile phase consisting of acetonitrile-water( 65∶ 35) at a flow rate of 1. 0 mL·min- 1. The column temperature was at 30 ℃ and the optimum detection wavelength of DAD was set at 245 nm. The drift tube and atomizer temperature of ELSD were 60,55 ℃, with a carrier gas( N 2) pressure of 20 psi. Result: The linear range of alisol C 23-acetate,Alisol A,alisol B and alisol B 23-acetate were 1. 869-29. 90 mg·L- 1( r = 0. 999 8),3. 731-74. 62 mg·L- 1( r = 0. 999 7),8. 653-138. 4 mg·L- 1( r =0. 999 9),4. 832-77. 31 mg·L- 1( r =0. 999 5),respeltively. The average recoveries( n = 6) were 98. 78%( RSD 2. 63%),98. 05%( RSD 2. 72%),98. 26%( RSD 2. 86%) and 97. 65%( RSD 2. 95%) respectively. Conclusion: The HPLC method is simple,rapid and accurate. This HPLC-DAD-ELSD verified method can be used for quantitative analysis of multi-component of Rhizoma Alismatis and provides a novel approach for evaluation of the quality of Rhizoma Alismatis comprehensively.