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

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.