Abstract:Objective:To study the plasma protein binding rate of methyl protodioscin.Method: The ultrafiltration was employed to determine the plasma protein binding rate of methyl protodioscin. The plasma concentrations of methyl protodioscin were measured by HPLC-MS-MS. Result:The plasma protein binding rate of methyl protodioscin with rat plasma at the concentration of 20.0, 100 and 200 μg·mL-1 were (94.6±0.16)%, (91.6±0.35)% and (86.10±0.60)%, respectively, while the plasma protein binding rate of methyl protodioscin with normal human plasma at the above concentrations were (82.11±5.12)%, (84.54±0.32)% and (88.52±1.02)%, respectively.Conclusion: The binding rate of methyl protodioscin with plasma protein is high.