An HPLC method for the determination of bisoprolol in human plasma and its application to a pharmacokinetic study.

A new high-performance liquid chromatographic method is described for the determination of bisoprolol in human plasma. The proposed method was based on the derivatization of bisoprolol with 4-chloro-7-nitro-2,1,3-benzoxadiazole in borate buffer at pH 9.5 to yield a fluorescent product. Chromatographic separation of bisoprolol was achieved by using isocratic elution at a flow rate of 1.2 mL/min on a C18 reversed-phase column (Inertsil, 4 μm, 150 4.6 mm) at 40°C. The mobile phase used for the analysis was methanol-water (70:30, % v/v). Fluorescence detector was used at the excitation and emission wavelengths of 458 and 525 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability. The assay was linear over the concentration range of 10-2000 ng/mL. This method was applied in pharmacokinetic studies of bisoprolol preparations in healthy volunteers.