Quantification of Serum Voriconazole, Isavuconazole, and Posaconazole by Liquid Chromatography Tandem Mass Spectrometry (LC‐MS/MS)

Voriconazole, isavuconazole, and posaconazole are triazole anti-fungal drugs commonly used to treat invasive fungal infections. Therapeutic drug monitoring is commonly carried out when patients are prescribed these drugs to ensure that the serum concentrations are sufficiently high for efficacy, but do not reach toxic concentrations. Mass spectrometric (MS) assays have been successfully utilized to determine the serum concentrations of these drugs. This protocol describes a sample preparation procedure and a liquid chromatography-tandem mass spectrometry assay for quantifying serum voriconazole, isavuconazole, and posaconazole in a single method. © 2018 by John Wiley & Sons, Inc.