Chromatographic-mass spectrometric analysis of peptidic analytes (2-10 kDa) in doping control urine samples.
This study developed and validated a unified chromatographic-mass spectrometric (LC-MS) method for detecting a broad range of prohibited peptide drugs (molecular mass 2–10 kDa) in doping control urine samples. The target analytes spanned five categories: insulins (human and animal-derived, including several analogues and a metabolite), growth hormone-releasing hormones (GHRHs) and their metabolites, insulin-like growth factors (IGF variants), synacthen, gonadorelin, and mechano growth factors. A key goal was simplifying sample preparation by consolidating what are traditionally separate, complex analytical workflows into a single procedure, controlled by five internal standards—one per peptide category. The method was validated as an initial testing procedure and shown to meet nearly all World Anti-Doping Agency (WADA) Minimum Required Performance Levels (MRPLs). As a proof of principle, the method was applied to authentic post-administration urine samples from human subjects dosed with insulins and gonadorelin, demonstrating real-world detection capability. Limitations include that human subject data are limited to proof-of-concept post-administration samples rather than a controlled efficacy or pharmacological trial, and the study's primary focus is analytical method development rather than clinical outcomes.
Why this grade: The study is an analytical method validation paper using authentic human post-administration urine samples only as a proof-of-concept demonstration, with no controlled trial design, randomization, or clinical endpoints.
Peptides with a molecular mass between 2 and 10 kDa that are prohibited in elite sports usually require dedicated sample preparation and mass spectrometric detection that commonly cannot be combined with other (lower molecular mass) substances. In most instances, the physicochemical differences are too significant to allow for a generic analytical procedure. A simplification of established and comparably complex analytical approaches is therefore desirable and has been accomplished in the context of this study. With urine samples representing still the most frequently collected doping control specimens, efficient extraction of peptidic analytes from this matrix was a major goal of this method, as demonstrated for the included compounds such as insulins (human, lispro, aspart, glulisine, tresiba, glargine metabolite, bovine insulin, porcine insulin), growth hormone-releasing hormones (sermorelin, CJC-1295, tesamorelin) incl. their respective metabolites, insulin-like-growth factors (long-R 3 -IGF-I, R 3 -IGF-I, des 1-3 -IGF-I), synacthen, gonadorelin and mechano growth factors (human MGF, MGF-Goldspink). Sample preparation and detection are controlled by five internal standards, covering all five included peptide drug categories. Nearly all requirements of the recent technical documents from the World Anti-Doping Agency (WADA) considering their minimum required performance levels (MRPL) are fulfilled, and the method was validated for its utilisation as initial testing procedure in doping controls. Finally, the approach was applied to authentic post-administration study urine samples (for insulins and gonadorelin) in order to provide proof of principle.
Educational summary of published research — not medical advice. License: cc by-nc-nd. Full text is shown only where licensing permits.