Rapid High Performance Liquid Chromatographic Assay for Determination of Voriconazole Concentration in Human Plasma
Kantima Sangsiriwut MSc*, Methee Chayakulkeeree MD, PhD**
Affiliation : * Department of Preventive and Social Medicine, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand ** Division of Infectious Diseases and Tropical Medicine, Department of Medicine, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Blood voriconazole level is affected by several factors and concentration of voriconazole in patient’s plasma is
crucial for treatment response.
Objective : To develop and validate a method of high performance liquid chromatography (HPLC) for determination of
plasma voriconazole level.
Material and Method: One-hundred and twenty microlitres of plasma sample was extracted with 6% perchloric acid. The
extracted plasma was separated on a reversed-phase C18 column with isocratic phase which consists of acetonitrile and
Milli-Q-water (68:32, vol/vol). The limits of quantitation, accuracy, precision, stability and recovery were validated. Plasma
samples from 10 patients receiving voriconazole during treatment of invasive fungal diseases were collected for voriconazole
assays.
Results : The lower limit of quantitation was 0.2 μg/mL. Linearity was demonstrated from 0.2 μg/mL to 20 μg/mL with 0.98
correlation coefficient value. Intra-day and inter-day variability of the voriconazole plasma concentration ranged from
0.78% to 3.01% and 1.52% to 4%, respectively. Accuracy ranges from 99.3%-101%. The extraction recovery ranges from
99.2%-101%. Plasma voriconazole level in patients showed significantly variable from patient to patient and the levels were
higher during the first 2 weeks of voriconazole treatment.
Conclusion : The present method is simple, accurate, and precise for measurement of voriconazole plasma concentrations
and can be applied for routine laboratory. Significant variability of voriconazole level in patient plasma highlights the
importance of therapeutic antifungal drug monitoring in patients receiving voriconazole.
Keywords : High performance liquid chromatography, HPLC, Voriconazole, Validation, Therapeutic drug monitoring, Antifungal agent
