Entwicklung massenspektrometrischer Nachweismethoden für dopingrelevante Analyten in Atemluft und getrockneten Blutstropfen als komplementäre Matrices im Anti-Doping Kontext

In the context of doping controls, urine and blood samples are well established matrices
for the detection of performance‐enhancing substances. However, these matrices are
associated with disadvantages, particularly with regard to their collection procedures,
logistical processes and financial aspects. For this reason, the interest in complementary
matrices has been growing constantly. The thesis presented herein describes
investigations regarding the applicability of exhaled breath and dried blood spots (DBS)
for doping control purposes as well as the development of detection methods using liquid
chromatography coupled with tandem mass spectrometry (LC‐MS/MS).
The first project focused on the development of a comprehensive LC‐MS/MS method for
a broad range of doping agents of low molecular weight for exhaled breath. The approach
was characterized in terms of selectivity, detection limits, identification limits, robustness,
carryover, matrix effects, and recovery. The applicability was demonstrated based on
several administration studies using doping‐relevant substances. In addition, the article
describes a system for simulating the exhaled breath aerosol, enabling the sample
collection device ExaBreath manufactured by SensAbues® to be characterized in terms of
sufficient efficiency and robustness.
The second project involved the conduction of exemplary excretion studies with the
doping agents propranolol and pseudoephedrine. After the oral application, exhaled
breath and DBS samples were collected and subsequently analyzed using LC‐MS/MS. For
data analysis, the sex of the study participants as well as cigarette consumption were
considered as possible impacting factors on the detectability of doping substances in
exhaled breath. The matrix was shown to be robust to the investigated parameters, but
significant inter‐ and intraindividual variations were detected with respect to the
determined concentrations in exhaled breath.
The third project emerged from the publication of a technical document by the World
Anti‐Doping Agency (WADA) establishing the application of DBS in the context of doping
controls. In order to address the resulting contribution of DBS samples to routine analysis,
a comprehensive detection method was developed comprising a total of 233 substances
representing all groups on the WADA's Prohibited List. The approach is characterized

a fully automated sample preparation with subsequent adaptive high‐resolution LCMS/
MS analysis. After validation in compliance with WADA guidelines, the method was
successfully implemented into routine analysis.
In the framework of this thesis important knowledge on the applicability of exhaled breath
and DBS for doping analysis was gained. It was shown that the detection of different
model substances in exhaled breath is generally feasible and can provide valuable
complementary information. However, the conduction of comprehensive application
studies is required in the future. The developed detection method for DBS is being
successfully applied in routine analysis and is characterized by its adaptability to new
developments in this field.