Determination of captopril in human plasma by RP-HPLC

OBJECTIVE: To establish a reversed phase high performance liquid chromatographic method for the determination of captopril in human plasma and to investigate the pharmacokinetics of captopril in Chinese healthy volunteers. METHODS: The drug was extracted from human plasma with ethyl acetate-benzene (1:1). The plasma concentrations of captopril were separated on a HYPERSIL C₁₈ column (4.6 mm x 250 mm, 5 μm) by Waters 510 HPLC. The mobile phase was a mixture of acetonitrile-1% acetic acid (45:55). The detection wavelength was 257 nm. RESULTS: A good linearity was obtained over the range of 6.25 to 800 μg·L^-1 in human plasma. The limit of detection was 6.25 μg·L^-1. The recoverys of method were from 101.00% to 108.88%. The precisions of intra-day and inter-day were in the rangs of 4.40%-7.88% and 2.87%-9.34%, respectively. CONCLUSION: The method is sensitive, accurate, reliable, and can be used in clinical research of captopril.