Analysis of endogenous steroids in urine by means of multi-immunoaffinity chromatography and isotope ratio mass spectrometry for sports drug testing

Putz, Marlen; Piper, Thomas; Dubois, Michel; Delahaut, Philippe; Thevis, Mario

doi:10.1007/s00216-019-02169-3

Cited by 7 publications

(3 citation statements)

References 35 publications

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“…e peak values of hip extension moment (P � 0.023), knee extension moment (P � 0.003), ankle plantar flexion moment (P < 0.001), and knee valgus moment (P � 0.028) have significant differences between the two different squats (Table 3). Except that the peak value of hip extension moment of restricted squat is greater than that of unrestricted squat [17], the peak value of knee extension moment, ankle plantar flexion moment, and knee valgus moment are greater than that of unrestricted squat.…”

Section: Results Analysismentioning

confidence: 74%

Analysis and Comparison of Motion Biomechanics Characteristics of Squat Jump and Half-Squat Jump

Zhao

Zhang

2022

Mobile Information Systems

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In order to study the biomechanical characteristics of squat jump and half-squat jump, analysis and comparison were made. This paper tests and analyzes the kinematics and dynamics of 63 young men’s squat jump, and synchronously collects the kinematics and dynamics data of subjects in the process of weight-bearing squat, in-situ free jump, and high platform landing. The experimental results showed that there was significant difference in knee joint angle at the time of toe off ( P < 0.05), and there was significant difference in ankle joint angle at the time of toe off ( P < 0.05). The time law of squat jump and semi squat jump in vertical jump was the same. In vertical jump, the reaction time law of squat jump and semi squat jump is the same, and the recovery standing time is the longest, followed by the take-off time and reaction time. The two vertical jump methods have no effect on the height, time, and speed of exercise take-off.

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Section: Results Analysismentioning

confidence: 74%

Analysis and Comparison of Motion Biomechanics Characteristics of Squat Jump and Half-Squat Jump

Zhao

Zhang

2022

Mobile Information Systems

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“…While increasing sample throughput by optimizing sample preparation protocols and/or analytical turnaround times is not necessarily critical in research projects, fast reporting times for doping control analyses are desirable during major national and international sporting competitions. Consequently, options to enhance the laboratory's efficiency have been further explored regarding IRMS in particular and in that context, the GC/C/IRMS strategy employed at the Games of the XXXI Olympiad (2016) was recently discussed by de Oliveira et al 85 Putz et al presented an approach employing immunoaffinity purification of TCs and ERCs instead of frequently utilized HPLC fraction collection in order to expedite the overall analysis time 86 . A volume of 2–3 ml of urine was preconcentrated by SPE and retained unconjugated steroidal analytes were removed by subsequent LLE prior to an enzymatic hydrolysis of glucurono‐conjugated TCs and ERCs.…”

Section: Anabolic Agentsmentioning

confidence: 99%

Annual banned‐substance review: Analytical approaches in human sports drug testing 2019/2020

Thevis

Kuuranne

Geyer

2020

Drug Testing and Analysis

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Analytical chemistry-based research in sports drug testing has been a dynamic endeavor for several decades, with technology-driven innovations continuously contributing to significant improvements in various regards including analytical sensitivity, comprehensiveness of target analytes, differentiation of natural/ endogenous substances from structurally identical but synthetically derived compounds, assessment of alternative matrices for doping control purposes, and so forth. The resulting breadth of tools being investigated and developed by anti-doping researchers has allowed to substantially improve anti-doping programs and data interpretation in general. Additionally, these outcomes have been an extremely valuable pledge for routine doping controls during the unprecedented global health crisis that severely affected established sports drug testing strategies. In this edition of the annual banned-substance review, literature on recent developments in antidoping published between October 2019 and September 2020 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified the World Anti-Doping Agency's 2020 Prohibited List.

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“…Several purification strategies are at the analyst’s disposal to separate target analytes from sample interferences, also referred to as a matrix, in carbon-CSIA sample preparation. These strategies range from offline chromatographic techniques using conventional solid-phase extraction (SPE) materials, , molecularly imprinted polymers (MIPs), cyclodextrin polymers, immunoaffinity chromatography, silica gel chromatography, , or ion-exchange chromatography to different types of online chromatographic purification techniques including size-exclusion chromatography or the most widely used reversed-phase (RP) high-performance liquid chromatography (HPLC). ,− While the target analytes are monitored in most of these works, this is not necessarily the case for all interferences. For example, consider 13 C/ 12 C measurement of atrazine in a groundwater extract containing interfering NOM, where chromatographic cleanup is warranted prior to GC-c-IRMS.…”

Section: Introductionmentioning

confidence: 99%

Quartz Crystal Microbalance as a Holistic Detector for Quantifying Complex Organic Matrices during Liquid Chromatography: 2. Compound-Specific Isotope Analysis

Wabnitz,

Chen,

Elsner

et al. 2024

Anal. Chem.

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In carbon-compound-specific isotope analysis (carbon CSIA) of environmental micropollutants, purification of samples is often required to guarantee accurate measurements of a target compound. A companion paper has brought forward an innovative approach to couple a quartz crystal microbalance (QCM) with high-performance liquid chromatography (HPLC) for the online quantification of matrices during a gradient HPLC purification. This work investigates the benefit for isotope analysis of polar micropollutants typically present in environmental samples. Here, we studied the impact of the natural organic matter (NOM) on the isotopic integrity of model analytes and the suitability of the NOM-to-analyte ratio as a proxy for the sample purity. We further investigated limitations and enhancement of HPLC purification using QCM on C 18 and C 8 phases for single and multiple targets. Strong isotopic shifts of up to 3.3% toward the isotopic signature of NOM were observed for samples with an NOM-to-analyte ratio ≥10. Thanks to QCM, optimization of matrix removal of up to 99.8% of NOM was possible for late-eluting compounds. The efficiency of HPLC purification deteriorated when aiming for simultaneous purification of two or three compounds, leading to up to 2.5% less NOM removal. Our results suggest that one optimized HPLC purification can be achieved through systematic screening of 3 to 5 different gradients, thereby leading to a shift of the boundaries of accurate carbon CSIA by up to 2 orders of magnitude toward lower micropollutant concentrations.

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Analysis of endogenous steroids in urine by means of multi-immunoaffinity chromatography and isotope ratio mass spectrometry for sports drug testing

Cited by 7 publications

References 35 publications

Analysis and Comparison of Motion Biomechanics Characteristics of Squat Jump and Half-Squat Jump

Analysis and Comparison of Motion Biomechanics Characteristics of Squat Jump and Half-Squat Jump

Annual banned‐substance review: Analytical approaches in human sports drug testing 2019/2020

Quartz Crystal Microbalance as a Holistic Detector for Quantifying Complex Organic Matrices during Liquid Chromatography: 2. Compound-Specific Isotope Analysis

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