超滤结合UHPLC-UV法测定川楝素在SD大鼠和新西兰兔中的血浆蛋白结合率OA

Objective:To establish a method for the determination of plasma protein binding of toosendanin.Methods:An ultrafiltra-tion tube with a cut-off value of 10 K was used to separate the SD rats and New Zealand rabbits plasma bound and free toosendanin,and the separation was carried out on a Waters UPLC ® BEH C18(2.1 mm × 100 mm,1.7 μm)column with an isocratic elution of acetoni-trile-0.1％phosphoric acid(31∶69)as the mobile phase,and the flow rate was 0.3 mL·min-1 at 25 ℃.Results:The linear range was 1-50 μg·mL-1,the LLOQ was 0.5 μg·mL-1,and the results of the methodological validation were within acceptable limits.The plasma protein binding rates of 5,10 and 20 μg·mL-1 toosendaninin SD rats were(77.01±3.45)％,(81.30±1.34)％and(83.89±2.78)％,respectively.The plasma protein binding rates at 3 concentrations of toosendaninin in New Zealand rabbit plasma was(64.09±4.66)％,(71.55±3.16)％,and(73.48±3.28)％,respectively.Conclusion:In vitro plasma protein binding of toosenda-nin did not show a concentration dependence with increasing plasma concentration of toosendanin,the binding rate was not affected by spe-cies,and there was almost no difference in protein binding between the plasma of SD rats and New Zealand rabbits.This research work can lay the foundation for further development and utilization of the medicinal value of toosendanin.