Anwendung von Dried Blood Spots (DBS) in der Dopinganalytik: eine innovative Probenmatrix für neue Kontrollstrategien in Training und Wettkampf

Publication: Book/ReportDissertations

Abstract

Abstract
A drop of whole blood dried on cellulose-based filter paper is an aspiring sampling technique for different fields of application, among others forensic toxicology and TDM. Recently, the technique has come in the focus of interest also in the arena of sports drug testing due to its multiple benefits. The minimal-invasive, straightforward and safe way of sampling can be highlighted.
Aim of the thesis presented was the development of analytical methods for the detection of analytes exhibiting different chemical properties including both small molecules and a peptide hormone with a higher molecular weight using DBS as sample matrix. Measurements were conducted by means of liquid chromatography coupled to high resolution/ high mass accuracy tandem mass spectrometry using a heated electrospray ion source operated in positive mode. On the basis of the methods developed here the numerous benefits of the emerging sampling technique could be demonstrated, such as the possibility for the direct analysis of intact anabolic steroid esters in blood. Not least in elite sports, the misuse of testosterone esters and related substances for performance enhancing purposes has a high prevalence. Consequently, a straightforward and reliable detection method is of eminent interest. Within the current approach a highly sensitive and specific method for the unambiguous proof of the illicit administration of exogenous testosterone esters was developed. Using the example of the labile peptide hormone Synacthen®, which is the synthetic analog of human adrenocorticotropin, the enhanced analyte stability in DBS was highlighted. Contrary to the rapid degradation in conventionally applied sample matrices, the loss of humidity and decreased enzymatic activity enabled for the first time the storage and detection of the peptide for several days. A highly sensitive initial testing procedure for Synacthen® based on a sophisticated sample preparation and the use of a nano-UPLC system was developed and validated. Additionally, the beneficial application of DBS as complementary sample matrix for the improvement of existing doping control strategies of frequently abused anabolic agents and stimulants was demonstrated. In the context of the approach presented, a sensitive method for the simultaneous determination of stanozolol, dehydrochloromethyltestosterone and pseudoephedrine was developed. According to the World Anti-Doping Code anabolic steroids are prohibited at all times, consequently frequent out-of-competition doping controls are required. On the contrary, stimulants are prohibited only during competition and the direct analysis of analyte concentrations in blood enables the determination of the presence or absence of pharmacologically relevant levels at the time of competition. A further milestone for the qualification of DBS analysis also in routine sports drug testing is the automation of the entire work-flow including extraction and purification of the samples and mass spectrometric detection. In doping control analysis, an automated system for the analysis of DBS was established for the first time. The chosen model compounds nicotine and its metabolites exemplified the practicability for high-throughput analysis.

Within the presented thesis the applicability of the emerging sample matrix DBS in the arena of sports drug testing was successfully demonstrated. Proof-of-concept was obtained by means of the analysis of authentic samples from administration studies with the respective target compounds. DBS are now available as complementary tool for the straightforward, safe and cost-effective collection of whole blood doping control samples. The considerable simplification of logistic aspects, including convenient storage and shipment conditions of the specimens as well as the possibility for the automation of the DBS analysis doping controls in large scale become available. Thus, surveillance of the compliance of anti-doping regulations can be performed also in recreational sports.
Original languageGerman
Place of PublicationKöln
PublisherDeutsche Sporthochschule Köln
Number of pages149
Publication statusPublished - 2016

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