DETERMINATION OF PRAVASTATIN IN RAT LIVER BY RP-HPLC

AIM　To establish a reverse-phase high performance liquid chromatographic method for the determination of pravastatin in rat liver. METHODS　An aliquot of 5 g liver homogenates, spiked with triamcinolone acetonide (internal standard), was extracted by solid-phase extraction with Bond Elut C₁₈ columns. Chromatography was performed using a C₁₈ reverse-phase column with mobile phase of Na₂HPO₄ buffer sdution (0.035 mmol·L^-1, pH 3.0)-acetonitrile (155∶42). RESULTS　The linear equation was Y=0.1843X-4.238×10^-3 (γ=0.9934) in the range of 0.05-10 μg·g^-1 liver. The limit of detection for pravastatin was 13 ng·mL^-1 (signal-to-noise ratio of 3), and the limit of quantification for pravastatin in liver homogenate was 50 ng·g^-1 liver (RSD<20%). The average extraction recovery of pravastatin from liver at different concentrations was 80.8%, and the average inter-day precision was 11%. This procedure was applied to assay pravastatin in rat liver which were collected from Lewis rats at different times after administration of pravastatin (ig 20 mg·kg^-1). CONCLUSION　The method was sensitive and is feasible for the pharmacokinetic and distribution study of pravastatin.