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Author Spotlight: Quantification of Complex Lipidomic Samples Using Stable Isotope Labeling
Published on: August 23, 2024
Practical strategies when using a stable isotope labeled microtracer for absolute bioavailability assessment: A case
Buyun Chen1, Pingping Lu2, Dugan Freeman3
1Genentech Inc., 1DNA Way, South San Francisco, CA 94080, United States.
Abstract:
The pH labile metabolite, hydrophobicity, high oral dose and systematic exposure of GDC-0810 posed tremendous challenges to develop a LC-MS method for a stable isotope labeled aBA study. In this study, we explored practical solutions to balance stability and sensitivity and to cope with the impact of high Cp.o. to Ci.v. ratio on the labeling selection and assay dynamic range. A [13C9] GDC-0810 was synthesized to minimize the isotopic interference between PO dose, internal standard and I.V. microtracer. A highly sensitive LC-MS assay was validated for quantitation of [13C9] GDC-0810 from 5 to 1250 pg/mL. The optimized method was applied to a proof of concept cynomolgus monkey aBA study and the bioavailability calculated using microtracer dosing and regular dosing were similar to each other.
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Assessing Body Temperature - Oral
Step 1:
Start by practicing proper hand hygiene to prevent the spread of microorganisms.
Step 2:
Take the thermometer out of the charging unit, switch it on, and wait for the ready sign.
Step 3:
Gently slide the probe cover until a click is heard. This simple action prevents cross-contamination and ensures the correct placement of the probe cover.
Step 4:
Instruct the patient to open their mouth and place...

