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Updated: Mar 8, 2026

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
Published on: March 9, 2018
Gauging circadian variation in ketamine metabolism by real-time breath analysis
P Martinez-Lozano Sinues1, M Kohler2, S A Brown3
1Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
Abstract:
The time-of-day of drug application is an important factor in maximizing efficacy and minimizing toxicity. Real-time in vivo mass spectrometric breath analysis of mice was deployed to investigate time-of-day variation in ketamine metabolism. Different production rates of ketamine metabolites, including the recently described anti-depressant hydroxynorketamine, were found in opposite circadian phases. Thus, breath analysis has potential as a rapid and 3Rs (Replacement, Reduction and Refinement) conforming screening method to estimate the time-dependence of drug metabolism.
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