Validation of a fast and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) with atmospheric pressure chemical ionization method for simultaneous quantitation of voriconazole, itraconazole and its active metabolite hydroxyitraconazole in human plasma

Abstract

Voriconazole and itraconazole are two broad-spectrum antifungal triazole derivates administered for the prevention and in the treatment of invasive fungal infections. Their broad inter- and intra-individual pharmacokinetic variability and the high probability of drug-drug interactions justify therapeutic drug monitoring. After liquid-liquid extraction with tert-butyl methyl ether, chromatographic separation was achieved on a Zorbax Eclipse XDB-C18 column using gradient elution with 10 mM ammonium formate and acetonitrile. Detection was performed by a tandem mass spectrometer coupled to LC via an atmospheric pressure chemical ionization (APCI) and quantification was performed using selected reaction monitoring (SRM) transitions Total run time was 4.5 min. The method was validated for concentrations ranging from 0.05 to 10 μg/mL for voriconazole and from 0.025 to 5 μg/mL for itraconazole and hydroxyitraconazole, respectively. The intra- and inter-day correlation coefficients of variation were <7.7%-<9.2%, respectively. The accuracy ranged from 92.6% to 109%. A rapid and simple liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC-APCI-MS/MS) method has been developed and validated to measure voriconazole itraconazole and hydroxyitraconazole in human plasma. This method is successfully applied to samples from patients receiving antifungal treatment.