AMPHOTERICIN-B DETERMINATION IN RESPIRATORY SECRETIONS BY REVERSED-PHASE LIQUID-CHROMATOGRAPHY

Direct delivery of amphotericin B (AMB) to the respiratory tract may b e an alternative to intravenous administration. The use of inhalation allows high AMB concentrations to be achieved at the site of infection . A reversed-phase high-performance liquid chromatographic method with a 30-mm-long column is described for assaying AMB in respiratory secr etions obtained by bronchoaspiration (BAS) and bronchoalveolar lavage (BAL). Sample clean-up involved treatment with methanol (BAS) and soli d-phase extraction onto Sep-Pak C-18 cartridges (BAL). The mobile phas e consisted of 2.5 mM Na(2)EDTA-acetonitrile (70:30, v/v). The retenti on time of AMB was 1.5 min. The range of the assay was from 0.1 to 5 m u g/ml. The mean recovery was over 90% for both fluids. Within-day and between-day RSDs ranged from 3.10 to 11.87%. AMB in the BAS samples w as stable for two days at 20-25 degrees C, fifteen days at 4 degrees C and for three months at -20 degrees C. The drug in the BAL fluid was stable for one day at 20-25 degrees C, seven days at 4 degrees C and f or one month at -20 degrees C. (C) 1998 Elsevier Science B.V. All righ ts reserved.