Simplified testing procedure for new potentially performance enhancing peptide hormones

Code: 19A14MT 

Several new performance enhancing peptides have necessitated particular attention of doping control laboratories. These peptides own significant energy modulating properties by acting as insulin receptor modulators (S507, S519). Athletes will benefit from these modulations and availability is given via internet-based sources for the non-approved candidates or via the pharmacy for approved compounds. For this study, peptides will be purchased, in-vitro metabolized and characterized by mass spectrometric methods. Afterwards, simple and fast detection methods will be developed by means of solid phase extraction and mass spectrometry. Ideally, it is aimed that these simplified methods will be combined with the already established assays for large peptides (insulin, GRFs etc.) to obtain one single multiplexed initial testing procedure for a large number of different prohibited peptides.

Main Findings: 

Due to their insulin mimetic properties, the two bioactive peptide-based drugs S519 and S597 represent prohibited compounds in sports. They act as selective insulin receptor modulators and can potentially trigger performance enhancing effects comparable to insulin or its analogs. So far, no analytical method exists to uncover the misuse of these peptides in sports. Within this study, a detection assay was developed to determine S519 and S597 in human plasma by means of liquid chromatography – mass spectrometry (LC-MS) after solid-phase extraction (SPE). The peptides together with their stable isotope labelled internal standards were custom synthesized and characterized by mass spectrometry. Moreover, the method was comprehensively characterized and found to show excellent specificity and sufficient limits of detection (< 0.5 ng/mL). In addition, different in-vitro experiments were conducted with both peptides and 15 different metabolic products were identified by means of high-resolution mass spectrometry (HRMS).