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The extraction and untargeted UHPLC-HRMS analysis of endogenous steroids in serum samples is described in this protocol. The employed full-scan acquisition mode provides the adequate sensitivity to highlight the main endogenous steroids present in blood, including mineralocorticoids, progestogens , and androgens. Technical aspects for both chromatography and mass spectrometry are discussed in detail, together with a proposition of setup for sample sequence and data analysis. Furthermore, general comments are given to help the assessment of data quality and system performance.

Recently, steroid hormones quantification in blood showed a promising ability to detect testosterone doping and interesting complementarities with the urinary module of the Athlete Biological Passport (ABP). In this work, an ultra-high pressure liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) method was developed for the quantification of eleven endogenous steroids in serum. The performance of the full scan and targeted SIM acquisition modes was evaluated and compared to the performance of tandem mass spectrometry (MS/MS). Passing-Bablok regressions and Bland-Altman plots were assessed for each analyte of interest, and concentration values measured by HRMS showed high correlation with the ones obtained by MS/MS for all target hormones, with low absolute differences in the majority of cases. A slight decrease in terms of sensitivity was observed with HRMS in both acquisition modes, but performing an analysis of variance multiblock orthogonal partial least squares (AMOPLS) on the dataset obtained with all three methods revealed that only 0.8% of the total variance was related to instrumentation and acquisition methods. Moreover, the evaluation of the testosterone administration effect over time highlighted testosterone itself and dihydrotestosterone as the most promising biomarkers of exogenous testosterone administration. This conclusion suggests that HRMS could provide suitable performance for blood steroid analysis in the anti-doping field., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This work describes the development of two methods involving supported liquid extraction (SLE) sample treatment followed by ultra-high performance liquid chromatography or ultra-high performance supercritical fluid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS and UHPSFC-MS/MS) for the screening of 43 anabolic agents in human urine. After evaluating different stationary phases, a polar-embedded C18 and a diol columns were selected for UHPLC-MS/MS and UHPSFC-MS/MS, respectively. Sample preparation, mobile phases and MS conditions were also finely tuned to achieve highest selectivity, chromatographic resolution and sensitivity. Then, the performance of these two methods was compared to the reference routine procedure for steroid analyses in anti-doping laboratories, which combines liquid-liquid extraction (LLE) followed by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). For this purpose, urine samples spiked with the compounds of interest at five different concentrations were analyzed using the three analytical platforms. The retention and selectivity of the three techniques were very different, ensuring a good complementarity. However, the two new methods displayed numerous advantages. The overall procedure was much faster thanks to high throughput SLE sample treatment using 48-well plates and faster chromatographic analysis. Moreover, the highest sensitivity was attained using UHPLC-MS/MS with 98% of the doping agents detected at the lowest concentration level (0.1ng/mL), against 76% for UHPSFC-MS/MS and only 14% for GC-MS/MS. Finally, the weakest matrix effects were obtained with UHPSFC-MS/MS with 76% of the analytes displaying relative matrix effect between -20 and 20%, while the GC-MS/MS reference method displayed very strong matrix effects (over 100%) for all of the anabolic agents., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The conditions for the analysis of selected doping substances by UHPSFC-MS/MS were optimized to ensure suitable peak shapes and maximized MS responses. A representative mixture of 31 acidic and basic doping agents was analyzed, in both ESI+ and ESI- modes. The best compromise for all compounds in terms of MS sensitivity and chromatographic performance was obtained when adding 2% water and 10mM ammonium formate in the CO2/MeOH mobile phase. Beside mobile phase, the nature of the make-up solvent added for interfacing UHPSFC with MS was also evaluated. Ethanol was found to be the best candidate as it was able to compensate for the negative effect of 2% water addition in ESI- mode and provided a suitable MS response for all doping agents. Sensitivity of the optimized UHPSFC-MS/MS method was finally assessed and compared to the results obtained in conventional UHPLC-MS/MS. Sensitivity was improved by 5-100-fold in UHPSFC-MS/MS vs. UHPLC-MS/MS for 56% of compounds, while only one compound (bumetanide) offered a significantly higher MS response (4-fold) under UHPLC-MS/MS conditions. In the second paper of this series, the optimal conditions for UHPSFC-MS/MS analysis will be employed to screen >100 doping agents in urine matrix and results will be compared to those obtained by conventional UHPLC-MS/MS., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The potential and applicability of UHPSFC-MS/MS for anti-doping screening in urine samples were tested for the first time. For this purpose, a group of 110 doping agents with diverse physicochemical properties was analyzed using two separation techniques, namely UHPLC-MS/MS and UHPSFC-MS/MS in both ESI+ and ESI- modes. The two approaches were compared in terms of selectivity, sensitivity, linearity and matrix effects. As expected, very diverse retentions and selectivities were obtained in UHPLC and UHPSFC, proving a good complementarity of these analytical strategies. In both conditions, acceptable peak shapes and MS detection capabilities were obtained within 7 min analysis time, enabling the application of these two methods for screening purposes. Method sensitivity was found comparable for 46% of tested compounds, while higher sensitivity was observed for 21% of tested compounds in UHPLC-MS/MS and for 32% in UHPSFC-MS/MS. The latter demonstrated a lower susceptibility to matrix effects, which were mostly observed as signal suppression. In the case of UHPLC-MS/MS, more serious matrix effects were observed, leading typically to signal enhancement and the matrix effect was also concentration dependent, i.e., more significant matrix effects occurred at the lowest concentrations., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Clenbuterol is a β2 agonist agent with anabolic properties given by the increase in the muscular mass in parallel to the decrease of the body fat. For this reason, the use of clenbuterol is forbidden by the World Anti-Doping Agency (WADA) in the practice of sport. This compound is of particular interest for anti-doping authorities and WADA-accredited laboratories due to the recent reporting of risk of unintentional doping following the eating of meat contaminated with traces of clenbuterol in some countries. In this work, the development and the validation of an ultra-high pressure liquid chromatography coupled to electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) method for the quantification of clenbuterol in human urine is described. The analyte was extracted from urine samples by liquid-liquid extraction (LLE) in basic conditions using tert butyl-methyl ether (TBME) and analyzed by UHPLC-MS/MS with a linear gradient of acetonitrile in 9min only. The simple and rapid method presented here was validated in compliance with authority guidelines and showed a limit of quantification at 5pg/mL and a linearity range from 5pg/mL to 300pg/mL. Good trueness (85.8-105%), repeatability (5.7-10.6% RSD) and intermediate precision (5.9-14.9% RSD) results were obtained. The method was then applied to real samples from eighteen volunteers collecting urines after single oral doses administration (1, 5 and 10μg) of clenbuterol-enriched yogurts., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The coupling of ultra high-pressure liquid chromatography with a single quadrupole mass spectrometer was investigated for the analysis of several cytochromes P450 (CYP450) substrates and respective metabolites. The effect of numerous operating parameters (e.g. mobile phase pH, flow rate, gradient length, MS acquisition mode, dwell time, polarity switching, etc.) on selectivity, sensitivity and acquisition rate was studied. It was demonstrated that basic pH conditions provided the best compromise in terms of sensitivity and chromatographic selectivity with both acidic and basic compounds. The optimal mobile phase flow rate for UHPLC-MS experiments should be comprised between 300 and 600 microL/min for 2.1mm ID columns, while a higher flow rate generated up to 3-fold loss in sensitivity. It was also demonstrated that the fast polarity switching mode represented a valuable tool to improve throughput, maintaining acceptable performance. Finally, limits of detection were included in the range [1-50 ng/mL] in positive ionization mode and [50-250 ng/mL] in negative ionization mode, for investigated compounds.