Rapid and sensitive high performance liquid chromatographic method for the determination of itraconazole and its hydroxy-metabolite in human serum.

Published high performance liquid chromatographic (HPLC) methods for the determination of itraconazole (ITZ) in biological matrices are labor intensive, extraction-based procedures which operate at a pH approaching the limit of column tolerance, and unless modified, cannot measure its hydroxy-metabolite (OH-ITZ). A protein precipitation-based method requiring no solvent extraction and utilizing a base-deactivated C18 analytical column to minimize peak tailing is described herein. Calibration curves for OH-ITZ and ITZ were linear from 25-1500 ng ml-1 (r2 > or = 0.999). Intra-assay relative standard deviations (R.S.D.) were below 12%. Inter-assay R.S.D. were below 14%. This method provides a rapid means for the accurate and precise determination of both OH-ITZ and ITZ concentrations in human serum.