Determination of illegal adulteration of dietary supplements with synthetic hair-growth compounds by UPLC and LC-Q-TOF/MS

In this study, we developed a UPLC-PDA and LC-Q-TOF/MS method to identify and measure the following prohibited substances that may be found in dietary supplements:triaminodil, minoxidil, bimatoprost, alimemazine, diphenylcyclopropenone, α-tradiol, finasteride, methyltestosterone, spironolatone, flutamide, cyproterone, dutasteride, and testosterone 17-propionate.The method was validated according to International Conference on Harmonization guidelines in terms of specificity, linearity, accuracy, precision, LOD, LOQ, recovery, and stability. The method was completely validated showing satisfactory data for all method validation parameters. The linearity was good (R² > 0.999) with intra- and inter-day precision values of 0.2–3.4% and 0.3–2.9%, respectively. Moreover, the intra- and inter-day accuracies were 87–102% and 86–103%, respectively, and the precision was better than 9.4% (relative standard deviation).Hence, the proposed method is precise and has high quality,and can be utilised to comprehensively and continually monitor illegal drug adulteration in various forms of dietary supplements. Furthermore, to evaluate the applicability of the proposed method, we analysed 13 hair-growth compounds in 78 samples including food and dietary supplements. Minoxidil and triaminodil were detected in capsules at concentrations of 4.69 mg/g and 6.54 mg/g. In addition, finasteride was detected in a tablet at 13.45 mg/g. In addition, the major characteristic fragment ions were confirmed once again using LC-Q-TOF/MS for higher accuracy.     

Screening for twenty-eight target anabolic-androgenic steroids in protein supplements using QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry

ABSTRACT

Anabolic-androgenic steroids (AASs) are very potent muscle builders, and professional sportsmen often take protein supplements to improve their performance. Several studies have emphasised that protein supplements may contain undeclared AASs banned by the International Olympic Committee/World Anti-Doping Agency. The widespread occurrence and abuse of contaminated protein supplements is extremely dangerous because of their side effects. To minimise the chances of an unattended positive doping test or to avoid serious health problems, adequate screening methods for the detection of a wide range of steroids is essential. To address this requirement, a rapid and effective modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method was developed and validated to screen and quantify the simultaneous analysis of twenty-eight AASs in protein supplements using LC-MS/MS. The validated method was applied to 198 protein supplements collected from on-line and, off-line markets, and direct purchase from overseas between 2019 and 2020. Of the 198 samples, two samples contained testosterone and stanozolol at concentrations of 0.27 μg/g and 0.023 μg/g, respectively. In addition, 5α-hydroxylaxogenin was detected for the first time in three products purchased in Korea from overseas. The modified QuEChERS method was established and successfully applied to screen and determine AASs as a measure of continuous control and supervision in protein supplements.     

Phosphodiesterase-5 inhibitors in Chinese tonic liquors by liquid chromatography coupled with quadrupole time of flight mass spectrometry

Chinese tonic liquor is an important dietary supplement in daily use, but it often happens that illicitly adulterated drugs in Chinese tonic liquor could lead to food safety issues. In this survey, an analytical method consisting of a liquid chromatography-quadrupole-time of flight mass spectrometer (LC-Q-TOF-MS), coupled with quick easy cheap effective rugged safe (QuEChERS) pretreatment, was established for identification of phosphodiesterase type 5 enzyme (PDE-5) inhibitors in Chinese tonic liquors. 86 PDE-5 inhibitors were qualitatively analysed by employing information dependent acquisition mass spectrometry (IDA-MS) in comparison with the accurate mass of the protonated molecular ion, isotopic pattern, library and chemical formula. This method was used to test 28 Chinese tonic liquor samples. The results revealed that the IDA-MS screening method is suitable for qualitative analysis of 86 PDE-5 inhibitors. Four samples were found to be adulterated with sildenafil, tadalafil, vardenafil, isopiperazinoafil, nortadalafil and desmethylsidenafil, which was 14.3% of the tested samples.