Quantitation of itraconazolein rat heparinized plasma by liquid chromatography-mass spectrometry

摘要

A liquid chromatographic—mass spectrometric (LC-MS) assay was developed and vali4ued for the determination of intraconazole (ITZ) in rat heparinized plasma using reversed-phase HPLC combined with positiw atmospheric pressure(API) mass spectrometry. After protein precipitation of plasma samples (0.1 ml) with acetonitrile containing .WDZ~tiOflfazodone as an internal standard (1.5.), a 50-pA aliquot of the supematant was mixed w~i 100 ~mJ of 10 mM ammoniumformate (pH 4.0). An aliquot of 25 pA of the mixture was injected onto a BDS Hypersil C~ 450X2 smu: 3 pm) at a flow-rate of 0.3 mi/mn. The mobile phase comprising of 10 mM ammonium formate pH 4~ aud acescunirde (60 40,v/v)was used in an isocratic condition, and ITZ was detected in single ion monitoring (SPA m~.. Standard curtes were linear (r230.994) over the concentration range of 4—1000 ng/ml. The mean predicted concentrati~ of the qualst~ control (QC) samples deviated by less than 10% from the coffesponding nominal values; the intra-ass.ay and unter-assay precision of the assay were within 8% relative standard deviation. Both ITZ and I.S. were stable in the injection selvern at room temperature for at least 24 h. The extraction recovery of ITZ was 96%. The validated assay was applied to a phamLacokinetic study of ITZ in rats following administration of a single dose of itraconazole (15 mg/kg).