Improved performance and maintenance in gas chromatography/isotope ratio mass spectrometry by precolumn solvent removal

von Flenker, Ulrich (Autor), ... Hebestreit, Moritz (Autor), Piper, Thomas (Autor), Hülsemann, Frank (Autor), Schänzer, Wilhelm (Autor)
Erschienen in Analytical chemistry, 79 (2007), 11, S. 4162-4168, Lit.

Investigations in carbon isotope ratios of seized testosterone and boldenone preparations

von Piper, Thomas (Autor), ... Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 14 (2022), 3 (Addressing the challenges in forensic drug chemistry II), S. 514-518, Lit.

Xenon elimination kinetics following brief exposure

von Schaefer, Maximilian S. (Autor), ... Piper, Thomas (Autor), Geyer, Hans (Autor), Schneemann, Julia (Autor), Neukirchen, Martin (Autor), Thevis, Mario (Autor), Kienbaum, Peter (Autor)
Erschienen in Drug testing and analysis, 9 (2017), 5/6, S. 666-670, Lit.

Sensitive detection of testosterone and testosterone prohormone administrations based on urinary concentrations and carbon isotope ratios of androsterone and etiocholanolone

von Piper, Thomas (Autor), ... Haenelt, Nadine (Autor), Fußhöller, Gregor (Autor), Geyer, Hans (Autor), Thevis, Mario (Autor)
Erschienen in Recent advances in doping analysis (29) : Proceedings of the Manfred Donike Workshop ; 39th Cologne Workshop on Dope Analysis 22nd to 26th March 2021, Hellenthal: Sportverl. Strauß (Verlag), 2021, S. 187-188, Lit.

Development of mass spectrometry-based methods for the detection of 11-ketotestosterone and 11-ketodihydrotestosterone

von Piper, Thomas (Autor), ... Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 15 (2023), 5, S. 566-578, Lit.

AICAr to SAICAr ratio can serve as additional marker of AICAr use

von Sobolevsky, Tim (Autor), ... Piper, Thomas (Autor), Ahrens, Brian (Autor), Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 14 (2022), 11-12, S. 2017-2025, Lit.

Sensitive detection of testosterone and testosterone prohormone administrations based on urinary concentrations and carbon isotope ratios of androsterone and etiocholanolone

von Piper, Thomas (Autor), ... Haenelt, Nadine (Autor), Fußhöller, Gregor (Autor), Geyer, Hans (Autor), Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 13 (2021), 11/12 (The 39th Manfred Donike workshop on doping analysis), S. 1835-1851, Lit.

An in vitro assay approach to investigate the potential impact of different doping agents on the steroid profile

von Piper, Thomas (Autor), ... Heimbach, Sonja (Autor), Adamczewski, Martin (Autor), Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 13 (2021), 5 (Non‐targeted screening of drugs), S. 916-928, Lit.

Monitoring 2-phenylethanamine and 2-(3-hydroxyphenyl)acetamide sulfate in doping controls

von Sigmund, Gerd (Autor), ... Dib, Josef (Autor), Tretzel, Laura (Autor), Piper, Thomas (Autor), Bosse, Christina (Autor), Schänzer, Wilhelm (Autor), Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 7 (2015), 11/12 (33rd Cologne workshop: Advances in sports drug testing), S. 1057-1062, Lit.

Investigations on changes in 13C/12C ratios of endogenous urinary steroids after pregnenolone administration

von Piper, Thomas (Autor), ... Schlug, Christoph (Autor), Mareck, Ute (Autor), Schänzer, Wilhelm (Autor)
Erschienen in Drug testing and analysis, 3 (2011), 5, S. 283-290, Lit.

Anabolic agents

von Piper, Thomas (Autor), ... Thevis, Mario (Autor)
Erschienen in Karch's drug abuse handbook, Boca Raton (Flor.): Routledge (Verlag), CRC Press (Verlag), 2022, S. 370-381, Lit.

A brief summary of different isotope ratio mass spectrometry-based approaches to detect low-dose testosterone applications

von Piper, Thomas (Autor), ... Thevis, Mario (Autor)
Erschienen in Recent advances in doping analysis (30) : Proceedings of the Manfred Donike Workshop ; 40th Cologne workshop on dope analysis ; 28th March to 1st April 2022, Hellenthal: Sportverl. Strauß (Verlag), 2022, S. 30-34, Lit.

Erythropoiesis-stimulating agents – from inorganic agents to biomolecules

von Reihlen, Philipp (Autor), ... Thomas, Andreas (Autor), Piper, Thomas (Autor), Krug, Oliver (Autor), Walpurgis, Katja (Autor), Thevis, Mario (Autor)
Erschienen in Karch's drug abuse handbook, Boca Raton (Flor.): Routledge (Verlag), CRC Press (Verlag), 2022, S. 383-398, Lit.

Addressing recent challenges in isotope ratio mass spectrometry: development of a method applicable to1-androstene-steroids, 6α-hydroxy-androstenedione, andandrostatrienedione

von Piper, Thomas (Autor), ... Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 14 (2022), 11-12, S. 1891–1903, Lit.

Studies on the in vivo metabolism of the SARM YK11 : Identification and characterization of metabolites potentially useful for doping controls

von Piper, Thomas (Autor), ... Dib, Josef (Autor), Putz, Marlen Svenja (Autor), Fußhöller, Gregor (Autor), Pop, Valentin (Autor), Lagojda, Andreas (Autor), Kuehne, Dirk (Autor), Geyer, Hans (Autor), Schänzer, Wilhelm (Autor), Thevis, Mario (Autor)
Erschienen in Drug testing and analysis, 10 (2018), 11/12 (36th Cologne workshop: Advances in sports drug testing), S. 1646-1656, Lit.

Optimization of an online heart-cutting multidimensional gas chromatography clean-up step for isotopic ratio mass spectrometry and simultaneous quadrupole mass spectrometry measure...

von Casilli, Alessandro (Autor), ... Piper, Thomas (Autor), Azamor de Oliveira, Fábio (Autor), Padilha, Monica Costa (Autor), Pereira, Henrique Marcelo Gualberto (Autor), Thevis, Mario (Autor), Aquino Neto, Francisco Radler de (Autor)
Erschienen in Drug testing and analysis, 8 (2016), 11/12 (34th Cologne workshop: Advances in sports drug testing), S. 1204-1211, Lit.

Determination of the origin of urinary norandrosterone traces by gas chromatography combustion isotope ratio mass spectrometry

von Hebestreit, Moritz (Autor), ... Flenker, Ulrich (Autor), Fußhöller, Gregor (Autor), Geyer, Hans (Autor), Güntner, Ute (Autor), Mareck, Ute (Autor), Piper, Thomas (Autor), Thevis, Mario (Autor), Ayotte, Christiane (Autor), Schänzer, Wilhelm (Autor)
Erschienen in The Analyst, 131 (2006), 9, S. 1021-1026, Lit.

Recent findings on 7-oxo-DHEA and its improved detection based on reference population-derived thresholds for 7β-OH-DHEA and 5αandrostane-3β,7β-diol-17-one

von Piper, Thomas (Autor), ... Geyer, Hans (Autor), Toboc, Ani (Autor), Ahrens, Brian (Autor), Pohanka, Anton (Autor), Thevis, Mario (Autor)
Erschienen in Recent advances in doping analysis (29) : Proceedings of the Manfred Donike Workshop ; 39th Cologne Workshop on Dope Analysis 22nd to 26th March 2021, Hellenthal: Sportverl. Strauß (Verlag), 2021, S. 45-49, Lit.

Carbon isotope ratios of endogenous steroids found in human serum : method development, validation, and reference population-derived thresholds

von Piper, Thomas (Autor), ... Geyer, Hans (Autor), Nieschlag, Eberhard (Autor), Bally, Lia (Autor), Thevis, Mario (Autor)
Erschienen in Analytical and bioanalytical chemistry, 413 (2021), 22 (Recent Trends in (Bio)Analytical Chemistry), S. 5655-5667, Lit.

Urine analysis concerning xenon for doping control purposes

von Thevis, Mario (Autor), ... Piper, Thomas (Autor), Geyer, Hans (Autor), Schaefer, Maximilian S. (Autor), Schneemann, Julia (Autor), Kienbaum, Peter (Autor), Schänzer, Wilhelm (Autor)
Erschienen in Rapid communications in mass spectrometry, 29 (2014), 1, S. 61-66, Lit.