Si ton booster à l’air trop fort pour être vrai, c’est probablement qu’il l’est (trop fort mais pas vrai)
Rapid assessment of the illegal presence of 1,3-dimethylamylamine (DMAA) in sports nutrition and dietary supplements using 1 H NMR spectroscopy.
Monakhova YB Drug Test Anal. 2014 Jun 9. doi: 10.1002/dta.1677. [Epub ahead of print]
1,3-Dimethylamylamine (DMAA) is a stimulant that can be found in pre-workout sports nutrition and dietary supplements. This practice is illegal because DMAA is not a safe food ingredient but rather an unapproved medicinal compound due to its pharmacological action. In order to determine the DMAA content in such products, a nuclear magnetic resonance (NMR) spectroscopic method was developed and validated (DMAA was quantified as DMAA-HCl). For quantification, the collective integral from two of the methyl groups of the molecule in the range δ 0.92-0.84 ppm was used. The method was linear over the examined range of 1-21 g/kg (R2 = 0.9937). The recoveries from spiked concentrations (0.1-6 g/kg) ranged between 85% and 105% (96% on average), with a relative standard deviation (RSD) of 1% for an authentic sample. The detection limit was 0.03 g/kg and the quantification limit was 0.08 g/kg (calculated for 75 mg sample weight). The actual DMAA-HCl content in the sample was quantified using calibration curves (external standardization) or 3,5-dinitrobenzoic acid as single-point internal standard. The developed NMR methodology was applied for the analysis of 16 products, from which 9 samples were found positive (the DMAA-HCl concentration varied between 3.1 g/kg and 415 g/kg). The method can be recommended for routine use in food testing, customs or doping control laboratories.
Voir aussi :
- Rôle de la sirtuine 1 dans l'hypertrophie
- De nouvelles cellules souches découvertes dans les muscles
- La natation: pas super efficace dans la chasse au gras
- Des hormones thyroïdiennes dans les suppléments boosters de thyroïde?
- Vitesse de détérioration de la whey dans des barres hyperprotéinées