Urine analysis concerning xenon for doping control purposes.

Area of Science:

• Sports Science
• Analytical Chemistry
• Forensic Toxicology

Background:

• Xenon was classified as a prohibited substance by the World Anti-Doping Agency (WADA) in September 2014.
• Xenon is categorized as a hypoxia-inducible factor (HIF) activator, making its detection in doping control samples desirable.
• Previous studies demonstrated xenon detection in blood and plasma; this study focuses on urine analysis.

Purpose of the Study:

• To develop and validate a method for detecting xenon in human urine for sports drug testing.
• To establish the detection window for xenon in urine samples.
• To provide a complementary analytical approach to existing methods for xenon detection.

Main Methods:

• Urine samples were enriched with xenon, diluted, and analyzed using gas chromatography/triple quadrupole mass spectrometry (GC/MS/MS) with headspace injection.
• Detection targeted three major xenon isotopes (m/z 128.9, 130.9, 131.9) in (pseudo) selected reaction monitoring mode for unambiguous identification.
• Assay validation included determination of limit of detection (LOD), precision, specificity, and analyte recovery. Method was applied to urine from patients post-xenon anesthesia.

Main Results:

• Xenon was detectable in enriched urine samples down to approximately 0.5 nmol/mL.
• The analytical method exhibited intraday and interday imprecision below 25% and demonstrated specificity in blank urine samples.
• Xenon was detected in patient urine samples up to 40 hours post-anesthesia, indicating the potential doping control detection window.

Conclusions:

• The developed GC/MS/MS method enables the unambiguous detection of xenon in urine, a common doping control specimen.
• This study provides crucial data on xenon's detectability in urine, complementing previous findings in blood and plasma.
• The method is fit-for-purpose for routine sports drug testing, aiding WADA in enforcing regulations against xenon use.