Historically, urine has been used for the detection of prohibited substances in sports. Since 2022, the use of dried blood spots and blood microsampling technologies has been approved. This sampling technique offers advantages (fast, non-intrussive sample collection; cheap and stable matrix, farmacokinetics). However, to allow the implementation new methods will need to be developed to allow for an adequate switch in sample matrix.

This project will focus on the development and validation of a wide-range of methods for doping substances at concentrations that will allow adequate detection. High performance chromatography-mass spectrometric methods will be developed and evaluated. Sveeral sample preparation (proteine precipitation, solid phase and liquid-liquid extraction) will be used and optimized. The influence of the hematocrit effect will be investigated and correction factors will be determined.

Once developed, the methods will be used in a diverse range of research projects as well as transferred to routine applications within and outside the doping context (e.g. endocrinology for the endogenous steroids, stimulants/narcotics to toxicology, etc). Hence, research networks will be set-up.

In a first phase, the new LC-MS will be used to develop methods in DBS and microsamples for a full steroid profile in blood. The developed methods will focus also on phase 2 metabolites and therefore offer a full range of target substances for doping and clinical applications. The methods would aim at the detection of the following steroids in adequate concentration ranges: Free steroids: testosterone, epitestosterone, androstenedione, dehydroepiandrosterone, dihydrotestosterone, androsterone, etiocholanolone, progesterone, 17a-OH-progesterone, cortisol, corticosterone, deoxycorticosterone, 11-deoxycorticosterone, 21-deoxycortisol, estradiol, estrone and intact conjugates: testosterone glucuronide, epitestosterone glucuronide, 5bab-androstanediol-3-glucuronide, 5bab-androstanediol-17-glucuronide, epiandrosterone glucuronide, testosterone sulfate, epitestosterone sulfate, androsterone sulfate, etiocholanolone sulfate, dehydroepiandrosterone sulfate

Indeed, one of the great advantages of DBS/microsampling offers the opportunity to apply the developed methods in other research fields, by focussing not only on androgens, but also estrogens, and other endogenous steroids in a clinically/pharmacokinetically relevant matrix. The additional steroids will make the methods suitable for applications for clinical applications. While certainly this will require additional effort, the scientific return can be tremendous. In the clinical field, the determination of steroid levels is critical for diagnosis, treatment and follow-up of androgen and estrogen levels in children and adults and follow-up of sexual development disorders and fertility. Improvements in the analytical field  facilitating easy sample collection and an improved pre-analytical phase are therefore important.

To achieve a full impact the cooperation with the department of endocrinology will be intensified and the method transferred. The joint-expertise of DoCoLab and the Department of endocrinology will allow to set-up the world-leading collaborative unit.