Objective: To develop a new method for the determination of astragaloside IV in Radix Astragali.
Method: A HPLC-ELSD method was set up, using Hypersil C18 column (150 mm x 4.6 mm), acetonitrile-water(1:2) as mobile phase with a flow rate of 1.0 ml.min-1. The parameters of drift tube and gas flow rate of the detector were set at 105 degrees C and 2.96 L.min-1 respectively.
Result: The calibration curve was linear in the range of 2.02-10.12 micrograms. The average recovery was 100.5%.
Conclusion: The active constituent astragaloside IV in Radix Astragali can be separated effectively. ELSD detection is appropriate for the determination of constituents with end absorption at low ultra-violet wavelengths.