Justin Mak1, Kirk K Sujishi2, Deborah French3. 1. UCSF Medical Center, USA. Electronic address: jzmak2@gmail.com. 2. UCSF Medical Center, USA. Electronic address: kirk.sujishi@ucsfmedctr.org. 3. Department of Laboratory Medicine, University of California, San Francisco, 185 Berry Street, Suite 290, San Francisco, CA 94107, USA. Electronic address: deborah.french@ucsf.edu.
Abstract
BACKGROUND: Voriconazole is an azole antifungal drug indicated for use in the treatment of invasive aspergillosis. Due to the large intra- and interindividual variation seen in voriconazole pharmacokinetics along with a high probability of drug-drug interactions, therapeutic drug monitoring is of considerable clinical value. As such, we developed and validated a LC-MS/MS assay to quantify serum voriconazole to improve turnaround time and decrease costs. METHODS: After protein precipitation with D3-voriconazole (deuterated internal standard) in acetonitrile was performed, samples were separated by gradient elution and injected into the mass spectrometer with a total run-time of 4 min per sample. Multiple reaction monitoring was employed using Q1/Q3 transitions of 350/127 and 350/281 for voriconazole and 353/284 and 353/127 for D3-voriconazole. RESULTS: Sample preparation took 30 min for 6 patient samples. The limit of quantitation was 0.1 μg/mL and the linearity ranged from 0.1 μg/mL to 10.0 μg/mL. Extraction recovery was ∼69% and ion suppression ∼13%. Intra- and inter-assay imprecision (%CV) was <5% at the limit of quantitation and <4% through the rest of the linear range. Method comparisons between our assay and two reference laboratory methods, HPLC-UV and LC-MS/MS, revealed mean biases of 11% and 4%, respectively. CONCLUSIONS: We have developed an accurate, rapid, and sensitive LC-MS/MS assay for quantification of human serum voriconazole. Our assay reduces current specimen volume requirements, decreases result turnaround time, and saves institutional funds.
BACKGROUND:Voriconazole is an azole antifungal drug indicated for use in the treatment of invasive aspergillosis. Due to the large intra- and interindividual variation seen in voriconazole pharmacokinetics along with a high probability of drug-drug interactions, therapeutic drug monitoring is of considerable clinical value. As such, we developed and validated a LC-MS/MS assay to quantify serum voriconazole to improve turnaround time and decrease costs. METHODS: After protein precipitation with D3-voriconazole (deuterated internal standard) in acetonitrile was performed, samples were separated by gradient elution and injected into the mass spectrometer with a total run-time of 4 min per sample. Multiple reaction monitoring was employed using Q1/Q3 transitions of 350/127 and 350/281 for voriconazole and 353/284 and 353/127 for D3-voriconazole. RESULTS: Sample preparation took 30 min for 6 patient samples. The limit of quantitation was 0.1 μg/mL and the linearity ranged from 0.1 μg/mL to 10.0 μg/mL. Extraction recovery was ∼69% and ion suppression ∼13%. Intra- and inter-assay imprecision (%CV) was <5% at the limit of quantitation and <4% through the rest of the linear range. Method comparisons between our assay and two reference laboratory methods, HPLC-UV and LC-MS/MS, revealed mean biases of 11% and 4%, respectively. CONCLUSIONS: We have developed an accurate, rapid, and sensitive LC-MS/MS assay for quantification of human serum voriconazole. Our assay reduces current specimen volume requirements, decreases result turnaround time, and saves institutional funds.
Authors: Christine L Skaggs; Greta J Ren; El Taher M Elgierari; Lillian R Sturmer; Run Z Shi; Nicholas E Manicke; Lindsey M Kirkpatrick Journal: Clin Chem Lab Med Date: 2020-04-28 Impact factor: 3.694