High-throughput screening for various classes of doping agents using a new 'dilute-and-shoot' liquid chromatography-tandem mass spectrometry multi-target approach.
Guddat. S S; Solymos. E E; Orlovius. A A; Thomas. A A; Sigmund. G G; Geyer. H H; Thevis. M M; Schänzer. W W
Key Findings
- dilute‑and‑shoot
- The metabolite of GHRP‑2 is detectable at concentrations as low as 1‑70 ng/mL, well below typical doping thresholds.
- The assay also simultaneously screens for diuretics, beta‑2 agonists, stimulants, SARMs, plasma expanders, and plasticizer metabolites.
Practical Outcomes
- For biohackers using GHRP‑2, this study shows that anti‑doping labs can now catch even tiny traces of the peptide’s metabolite, so using it could risk a positive test. The method’s simplicity means labs can screen many substances quickly, but it doesn’t provide new dosing or efficacy guidance for the peptide itself.
Summary
Scientists created a fast, simple urine test that can spot many banned substances, including a breakdown product of the growth‑hormone‑releasing peptide GHRP‑2, at very low levels. The method needs no complex prep and can handle many drugs at once, making it useful for anti‑doping labs.
Abstract
A new multi-target approach based on liquid chromatography--electrospray ionization tandem mass spectrometry (LC-(ESI)-MS/MS) is presented to screen for various classes of prohibited substances using direct injection of urine specimens. With a highly sensitive new generation hybrid mass spectrometer classic groups of drugs--for example, diuretics, beta2-agonists--stimulants and narcotics are detectable at concentration levels far below the required limits. Additionally, more challenging and various new target compounds could be implemented. Model compounds of stimulant conjugates were studied to investigate a possible screening without complex sample preparation. As a main achievement, the integration of the plasma volume expanders dextran and hydroxyethyl starch (HES), commonly analyzed in time-consuming, stand-alone procedures, is accomplished. To screen for relatively new prohibited compounds, a common metabolite of the selective androgen receptor modulator (SARMs) andarine, a metabolite of growth hormone releasing peptide (GHRP-2), and 5-amino-4-imidazolecarboxyamide ribonucleoside (AICAR) are analyzed. Following a completely new approach, conjugates of di(2-ethylhexyl) phthalate (DEHP) metabolites are monitored to detect abnormally high levels of plasticizers indicating for illicit blood transfusion. The assay was fully validated for qualitative purposes considering the parameters specificity, intra- (3.2-16.6%) and inter-day precision (0.4-19.9%) at low, medium and high concentration, robustness, limit of detection (1-70 ng/ml, dextran: 30 µg/ml, HES: 10 µg/ml) and ion suppression/enhancement effects. The analyses of post-administration and routine doping control samples demonstrates the applicability of the method for sports drug testing. This straightforward and reliable approach accomplishes the combination of different screening procedures resulting in a high-throughput method that increases the efficiency of the labs daily work.
Study Information
pubmed
2011
2011-12-02T00:00:00.000Z
10.1002/dta.372
77
43