HPLC determination of the content and entrapment efficiency of β-elemene liposome

Objective:To establish an HPLC method for determining the content and entrapment efficiency of β- elemene liposome.Methods:HPLC analysis was performed on a Diamonsil C_(18)column(4.6 mm×200 mm,5 μm) with mobile phase of acetonitrile-water(80:20)at the flow rate of 1.0 mL·min~(-1).The injection volume was 20 μL.The UV detection wavelength was set at 210 nm.The column compartment temperature was set at 25 ℃.For as- say of liposome entrapment efficiency,Sephadex G-50 was used for removing the free β-elemene before sample preparation of HPLC analysis.Results:β-elemene had a good linear relation in the range of 5.0-60.0 μg·mL~(-1) (r=0.9994).The precision(RSD)was 1.4%-4.2%(n=5),the reproducibility(RSD)was 3.1%(n=5), the average recovery rate was 101.8%(n=15).Conclusion:The developed method is simple,accurate and relia- ble for determination of the content and entrapment efficiency of β-elemene liposome.