Determination of Plasma Protein Binding Rate of Salvianol Acid A by Ultrafiltration

Objective:To establish a method for the determination of salvianolic acid A in the plasma samples,and then study the plasma protein binding rate of salvianolic acid A.This can provide a reference to the further study of salvianol acid A in its metabolism,pharmacokinetics and clinical treatment.Method:The ultrafiltration was employed to determine the plasma protein binding rate of salvianol acid A in BSA plasma samples,rat plasma samples,the New Zealand rabbit plasma samples and beagle dog plasma samples.The plasma concentrations of salvianol acid A were measured by RP-HPLC.Result:The calibration curve of salvianolic acid A was linear within the ranges of 0.01-2.5 mg · L-1(r=0.999 4).The average plasma protein binding rates of salvianol acid A with BSA,rat plasma,the New Zealand rabbit plasma and beagle dog plasma were(99.79±0.02)%,(99.79±0.03)%,(99.73±0.06)%,(99.81±0.03)% in the plasma concentrations of 5.0,50.0,100.0 mg · L-1 respectively.Conclusion:The method has high sensitivity,good specificity and reproduction,with simple management thus fulfilling the requirement.Salvianol acid A shows a high binding power to plasma protein.,and this was independent of the investigated concentrations and the different species.