Determination of prohibited, small peptides in urine for sports drug testing by means of nano-liquid chromatography/benchtop quadrupole orbitrap tandem-mass spectrometry.
Thomas. Andreas A; Walpurgis. Katja K; Krug. Oliver O; Schänzer. Wilhelm W; Thevis. Mario M
Key Findings
- A nano‑LC/Orbitrap method was created to screen 11 prohibited small peptides in urine.
- The detection limit for GHRP‑2 is extremely low (2‑10 pg/mL).
- The assay showed good specificity, recovery (45‑95%), and precision (<20% at 100 pg/mL).
Practical Outcomes
- Because the test can catch very low levels of GHRP‑2, biohackers should know that even small doses may be detected in anti‑doping screens. Timing of use or avoiding the peptide altogether may be necessary if drug testing is a concern.
Summary
The paper describes a new urine test that can spot tiny amounts of banned peptides like GHRP‑2, showing it can detect as little as a few picograms per milliliter.
Abstract
In the present study, a screening assay was developed comprising 11 prohibited peptides (<1.5 kDa) that are sufficiently purified from urine using weak cation exchange with subsequent determination of all substances by means of nanoUHPLC separation coupled to high resolution tandem mass spectrometry. These peptides included Gonadorelin (LH-RH), Desmopressin and 9 growth hormone releasing peptides (GHRP-1, -2, -4, -5, -6, Hexarelin, Alexamorelin, Ipamorelin and a GHRP-2 metabolite); however, the procedure is expandable to further target analytes or metabolites. The method was validated with a main focus on qualitative result interpretation considering the parameters specificity, linearity (0-500 pg/mL), recovery (45-95%), precision (<20% at 100 pg/mL), limits of detection (2-10 pg/mL), robustnesss and ion suppression. The proof-of-principle was shown by analysing excretion study urine samples for LHRH, Desmopressin and GHRP-2.
Study Information
pubmed
2012
2012-07-28T00:00:00.000Z
10.1016/j.chroma.2012.07.022
59
24