High-performance liquid chromatography assay of amiodarone in rat plasma.

Abstract

PURPOSE: A high-performance liquid chromatographic method is described for the determination of amiodarone in rat plasma. METHODS: After liquid-liquid extraction, the separation of amiodarone from internal standard and endogenous components was accomplished using reversed phase chromatography. The mobile phase, a combination of monobasic potassium phosphate, methanol and acetonitrile, was run isocratically through a C(8) analytical column. The UV detection was at 254 nm for ethopropazine, the internal standard, and subsequently changed to 242 nm for amiodarone detection. RESULTS: Analytical run time was less than 13 min. Mean recovery was 75% and 82% for lower (0.5 microg/ml) and higher concentrations (5 microg/ml), respectively. The assay exhibited excellent linear relationships between peak height ratios and plasma concentrations; quantitation limit was at least 0.035 microg/ml, based on 100 microl of rat plasma. Accuracy and precision were <17% over the concentration range of 0.035 to 5 microg/ml. CONCLUSION. The assay was applied successfully to the measurement of amiodarone plasma concentrations in rats given the drug orally.