Simultaneous Estimation of Amiodarone and Desethylamiodarone in Human Plasma by High- Performance Liquid Chromatographic Method

A high performance liquid chromatographic method is described for simultaneous estimation of amiodarone and its metabolite desethylamiodarone in plasma. After precipitation with acetonitrile, the separation of amiodarone, desethylamiodarone and internal standard was accomplished using reversed phase chromatography. The mobile phase, a combination of ammonium acetate (pH 3.5 adjusted with ortho phosphoric acid) and acetonitrile was run isocratically through a C18 analytical column. The UV detection was done at 242 and 247 nm for amiodarone and desethylamiodarone respectively. Analytical run time was 10 min. Mean recovery was 84% for 0.5 μg/ml concentrations. The assay exhibited good linear relationship between peak height ratios and plasma concentration. Quantification limit was at least 0.01 μg/ml of amiodarone and desethylamiodarone. Accuracy and precision were over the concentration range of 0.01-10 μg/ml. Assay was successfully applied to the measurement of amiodarone and its metabolite desethylamiodarone in human plasma of patients who were on long-term oral therapy on amiodarone.