Determination astragaloside IV in Radix Astragali by HPLC-ELSD

Objective:To determine astragaloside Ⅳ in Radix Astragali by HPLC-KLSD. Methods:Radix Astragali was extracted with MeOH-NH3·H2O( v/v 9:1), the condition was confirmed and the validation of the method was also tested. The chromatogra phy condition was with Hypersil ODS 2 column (4. 6mm×250mm,5μm); mobile phase was A; ACN ,B: H2O, gradient elutron,flow speed was 1.0 ml/min, temperature of column was room temperature, inject volume: 20μL. The KLSD conditions were as follows: the temperature of drift tube was 40℃, the gas pressure was 3. 5Bar, the value of gain was 7. Results:The intra-day and mter-day precision (RSD)at low, middle and high injection amount were all less than 2. 0%. The stability ( RSD) was 1. 24% in 48h. The re(?)-rence (RSD, n=5) was 1.26%. The limit of detection was 0. 6930mg/mL The recoveries were 97.05% (KSD=0. 17%, n =3) for astragaloside Ⅳ. The contents of astragaloside Ⅳ in (en different batch of Astragalus membranaceus (Fisch. ) Bge. were accord to the standard of Chinese Pharmacopoeia. Conclusion:The method covild shorten the process and time of Radix Astragali pretreatment with character of simple, suitable and reliable. The studies could apply to determine the content of astragaloside Ⅳ in Radix Astragalt.