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bioRxiv · 10.1101/685230

Targeting the Administration of Ecdysterone in Doping Control Samples

Abstract

PurposeThe phytosteroid ecdysterone was recently reported to enhance performance in sports and may thus be considered as a substance of relevance in anti-doping control. To trace back an administration of ecdysterone from urine samples analytical properties have been investigated to assess its integration into initial testing procedures (ITP) in doping control laboratories.\n\nMethodsAnalytical properties of ecdysterone were evaluated using GC-QTOF-MS and LC-QTOF-MS. Its metabolism and elimination in human were studied using urines collected after administration.\n\nResultsThe detectability of ecdysterone by GC-MS (after derivatization) and/or LC-MS(/MS) has been demonstrated and sample preparation methods were evaluated. Dilute-and-inject for LC-MS(/MS) or SPE using Oasis HLB for GC-MS or LC-MS were found most suitable, while liquid-liquid extraction was hampered by the high polarity of ecdysteroids.\n\nMost abundantly, ecdysterone was detected in the post administration urines as parent compound besides the metabolite desoxy-ecdysterone. Additionally desoxy-poststerone was tentatively assigned as minor metabolite, however further investigations are needed.\n\nConclusionAn administration of ecdysterone can be targeted using existing procedures of anti-doping laboratories. Ecdysterone and desoxy-ecdysterone appeared as suitable candidates for integration in ITP. Using dilute-and-inject a detection of the parent compound was possible for more than two days after the administration of a single dose of ~50 mg.

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BibTeXRIS

Parr, M. K., Ambrosio, G., Wuest, B., Mazzarino, M., de la Torre, X., Sibilia, F., Joseph, J. F., Diel, P., Botre, F.. 2019-06-27. Targeting the Administration of Ecdysterone in Doping Control Samples. https://doi.org/10.1101/685230

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