The objective of this study is to establish a quantitative method for simultaneous determination of costunolide and dehydrocostuslactone in Xin-ke-shu preparations. The HPLC quantitative analysis was established on a Hypersil BDS column (100x 4.6 mm, 2.4 μm, Thermo) with UV detection at 225 nm. The mobile phase was water and methanol (30:70, v/v), and used at a flow rate at 0.5 mL·min- 1 . The established method showed a good linearity (R2 > 0.9999) over the investigated concentration ranges (0.07-2.80 μg), good inter-day and intra-day precisions (less than 3%) and good recoveries (from 99.82% to 99.98%) for both target compounds. The method was found to be suitable for simultaneous determination of costunolide and dehydrocostuslactone in Xin-ke-shu preparations and can be used as a comprehensive approach to the previous reported quality control of Xin-ke-shu preparations.
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