title: Determination of amphotericin B, liposomal amphotericin B, and amphotericin B colloidal dispersion in plasma by high-performance liquid chromatography.
abstract: Amphotericin B is a potent polyene antifungal drug for intravenous treatment of severe infections. It is used as amphotericin B-deoxycholate and in order to reduce amphotericin B toxicity as lipid-formulated complex (liposomal or colloidal dispersion). A sensitive and specific analytical method is presented for the separation of lipid-complexed and plasma protein-bound amphotericin B in human heparinized plasma. This separation, which is required for pharmacokinetic studies, is achieved by solid-phase extraction (SPE) via Bond Elut C18. The protein-bound amphotericin B has a higher affinity to the SPE material and is therefore retained, whereas the lipid-complexed amphotericin B is eluted in the first step. The recovery of the SPE was >75% for high concentrations and >95% for low concentrations. Quantification was performed by reversed-phase HPLC using a LiChrosorb-RP-8 column, UV detection (lambda=405 nm) and a mixture of acetonitrile-methanol-0.010 M NaH2PO4 buffer (41:10:49, v/v) as mobile phase. The retention time for amphotericin B under the given conditions was 6.7 min. The calibration curves were found to be linear (r > or = 0.999) in two different ranges (5.0-0.50 microg/ml and 0.50-0.005 microg/ml). Intra- and inter-day precision and accuracy fulfilled the international requirements. No interference from other drugs (typical broad medication for intensive-care patients) or common plasma components was detected in >400 samples analyzed.
authors.affiliation: Department of Medicine, Innsbruck University Hospital, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Egger
authors.forename: R
authors.initials: R
authors.lastname: Bellmann
authors.forename: C J
authors.initials: CJ
authors.lastname: Wiedermann
mesh_terms: D000666:Amphotericin B / Q000097:blood* / Q000493:pharmacokinetics; D000935:Antifungal Agents / Q000097:blood* / Q000493:pharmacokinetics; D019540:Area Under Curve; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003422:Critical Care; D016903:Drug Monitoring; D006801:Humans; D008081:Liposomes; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000935:Antifungal Agents; D008081:Liposomes; D000666:Amphotericin B