RESUMEN
Objective To develop a method for determination of the plasma protein binding rate of bisoprolol in human plasma by high performance liquid chromatography ( HPLC) combined with hollow fiber-based liquid-phase microextraction ( HF-LPME) . Methods Method of liquid phase microextraction was optimized. The concentration of bisoprolol in the reconstitute solution was analyzed by HPLC. The mobile phase consisted of water-methanol-acetonitrile-0. 1% phosphoric acid (50:34:6:10). The excitation wavelength was 232 nm and emission wavelength was 300 nm. Through the linear regression equations, the total and free concentrations were obtained, and then the protein binding rate was calculated. Results At low, middle, and high concentration, the protein binding rate of bisoprolol was 31. 2%, 32. 0% and 31. 8%, respectively. Conclusion The proposed method is proven to be simple, fast and reproducible, and is feasible for the determination of plasma protein binding rate of bisoprolol. Bisoprolol moderately binds with plasma protein independent of concentration.