目的:测定熊果苷的大鼠血浆蛋白结合率。方法:采用平衡透析法模拟熊果苷体内与血浆蛋白结合的过程,并建立测定透析袋内血浆和袋外透析液中样品的高效液相色谱-质谱联用(HPLC-MS/MS)方法:测定低、中、高三个浓度(50、200和1000 ng·m L-1)的熊果苷在透析袋内血浆中的浓度与透析袋外缓冲液中的浓度,计算血浆蛋白结合率。结果:低、中、高三个浓度的熊果苷在体外与大鼠的平均血浆蛋白结合率分别为85.8%、83.2%和87.2%,三个浓度之间的血浆蛋白结合率没有显著差异(P>0.05)。结论:熊果苷与大鼠血浆蛋白呈中高度结合。 Objective: To determine the plasma protein binding rate of arbutin in rats. Methods: The process of binding of arbutin to plasma proteins was simulated by equilibrium dialysis. HPLC-MS / MS method was established for the determination of plasma samples in dialysis bags and dialysate in bags. The concentration of arbutin in the dialysis bag plasma and the concentration in the buffer solution outside the dialysis bag were measured to determine the plasma protein binding rate of low, middle and high concentrations of arbutin (50,200 and 1000 ng · m L -1). RESULTS: The mean plasma protein binding rates of arbutin at low, medium and high concentrations were 85.8%, 83.2% and 87.2% in vitro, respectively. There was no significant difference in plasma protein binding between the three concentrations (P > 0.05). Conclusion: Arbutin has a moderate to high level of plasma protein in rats.