Quattro premier xe lc ms ms

Quantification of hydroxychloroquine in plasma and lung tissues of infected hamsters was performed by a sensitive and selective validated high-performance liquid chromatography coupled with tandem mass spectrometry method (Quattro Premier XE LC-MS/MS, Waters), with lower limits of quantification of 0.015 μg/mL for plasma and 0.05 μg/mL for lung tissue (Doudka et al., 2020 ). Plasma samples and lung tissue homogenates were collected at euthanasia, 14 h after last drug intake of 3 days of treatment. Hydroxychloroquine was extracted by a simple protein precipitation method, using methanol and ice-cold acetonitrile for plasma and lung tissue homogenates respectively, as previously described (Maisonnasse et al., 2020 (link)). Briefly, 100 μL of sample matrix spiked with 10 μL of internal standard working solution (HCQ-d5, Alsachim) was vortexed for 2 min and then centrifuged at 4 °C for 10 min. Tissue-homogenate supernatants were evaporated. Dry residues or plasma supernatants were then transferred to 96-well plates and 5 μL was injected. To assess the selectivity and the specificity of the method and matrix effect, blank plasma and lung tissue homogenates from untreated hamsters were processed and compared with HCQ and internal standard-spiked samples from the same untreated controls animals.