Background Amiodarone has been widely dispensed as capsules prepared in the pharmacy department for paediatric patients. A stability study was performed with these capsules to determine their expiry date. However the European Pharmacopoeia High Performance Liquid Chromatography (HPLC) method was not performed because of a worldwide shortage of acetonitrile at the beginning of our stability study.

Purpose The purpose was to develop a HPLC assay of amiodarone capsules that did not use acetonitrile.

Materials and methods The authors developed the assay on a chromatographic system consisting of a Spectra-Physics Analytical HPLC chain. The column used was a C18 (120Ä, 250 mm x 4.6 mm, 5 µm). The mobile phase was 0.01 M phosphate buffer pH 2.30 + methanol (17/83 v/v) with a flow rate of 1 ml/min. The sample injection volume was 20 µL. The analysis time was 15 min. The validation study was performed according to ICH. The chromatography parameters (retention time, number of theoretical plates, tailing factor, capacity factor) were calculated to study the system suitability test. Specificity (interference from mannitol, excipient), linearity, precision (repeatability and intermediate precision) and accuracy checks were performed.

Results In chromatographic conditions, amiodarone retention time was 7.47 minutes. The capacity factor and the number of theoretical plates were respectively 1.34 and 5,313. The tailing factor did not exceed 1.5. No interference from mannitol could be observed at 242 nm. Within the assay range, amiodarone concentration was linearly related to absorbance at 242 nm. The repeatability and the intermediate precision were demonstrated because relative SD was less than 2%. The method is accurate because the 100% value was within the confidence limits.

Conclusions The method developed in this study has the advantage of being simple, precise, accurate and convenient. This method is applicable for qualitative and quantitative amiodarone capsules. The results are accurate and precise and confirmed by statistical parameters.