Fast analysis of doping agents in urine by ultra-high-pressure liquid chromatography–quadrupole time-of-flight mass spectrometry

Approach to chemometrics models by artificial neural network for structure: first applications for estimation retention time of doping agent

“…The data set, used in this study, is the retention time (RT) of doping agents in urine (a total number of 103 molecules), which obtained by ultra-high-pressure liquid chromatography-quadrupole timeof-flight mass spectrometry (UHPLC-QTOF-MS) were taken from the literature [25] is shown in Table 1. The prohibited list covers nine pharmaceutical classes of substances (e.g., stimulants, diuretics, anti-estrogens), three forbidden doping methods (e.g., enhancement of oxygen transfer, chemical and physical manipulation and gene doping), and two groups of analytes prohibited in specific activities (e.g., alcohol,  -blockers).…”

Annual banned‐substance review: analytical approaches in human sports drug testing

“…Two separate analyses (positive and negative electrospray ionization) in full scan mode were conducted requiring 9 min each, and detection limits for respective aromatase inhibitors and anti-estrogens ranged between 5 and 25 ng/mL. [73] Both methods target the active drugs only; however, by including major metabolites the detection windows may be prolonged and detection limits may also be improved in both analytical setups. These aspects were considered in a third screening procedure based on GC-MS and targeting letrozole, aminoglutethimide, anastrozole, and the metabolites hydroxyl-bisdesacetyl-cyclofenil, hydroxymethoxy-tamoxifen, and hydroxylclomiphene in a comprehensive analytical approach.…”

“…These protocols rely on generic sample preparation methods based on solid phase extraction, [74] liquid-liquid extraction [72,75] the direct injection of the diluted urine sample. [73] Due to the diverse nature of the group, the diuretics are, among several other classes of prohibited substances (most often e.g. betablockers, stimulants, narcotics and anti-estrogens), included in the protocols to demonstrate the applicability and flexibility of the developed universal screening method.…”

“…[88] Stimulants were also included in the multianalyte methods in which hundreds of target compounds are analyzed in urine with minimal sample preparation and LC-MSbased screening methods. [72,73] An interesting GC/MS application was developed for the analysis of 150 prohibited substances, stimulants among them, combining simultaneous operations of full scan and SIM modes, which is an attractive alternative with respect to the reliable identification of stimulants of low molecular weight. [3] …”

“…clomiphen). [72,73] One approach relied on conventional sample-preparation steps including enzymatic hydrolysis and LLE followed by LC-MS/MS analysis operating a tripe quadrupole instrument operated in multiple reaction monitoring (MRM) mode. A single analytical run was completed within 19 min allowing detection limits of 30-50 ng/mL for the active drugs in urine specimens.…”