title: Simplifying and expanding the screening for peptides <2 kDa by direct urine injection, liquid chromatography, and ion mobility mass spectrometry.
abstract: The analysis of low-molecular-mass peptides in doping controls has become a mandatory aspect in sports drug testing and, thus, the number of samples that has to be tested for these analytes has been steadily increasing. Several peptides <2 kDa with performance-enhancing properties are covered by the list of prohibited substances of the World Anti-Doping Agency including Desmopressin, LH-RH, Buserelin, Triptorelin, Leuprolide, GHRP-1, GHRP-2, GHRP-3, GHRP-4, GHRP-5,GHRP-6, Alexamorelin, Ipamorelin, Hexarelin, ARA-290, AOD-9604, TB-500 and Anamorelin. With the presented method employing direct urine injection into a liquid chromatograph followed by ion-mobility time-of-flight mass spectrometry, a facile, specific and sensitive assay for the aforementioned peptidic compounds is provided. The accomplished sensitivity allows for limits of detection between 50 and 500 pg/mL and thus covers the minimum required performance level of 2 ng/mL accordingly. The method is precise (imprecision <20%) and linear in the estimated working range between 0 and 10 ng/mL. The stability of the peptides in urine was tested, and -20°C was found to be the appropriate storage temperature for sports drug testing. Finally, proof-of-concept was shown by analysing elimination study urine samples collected from individuals having administered GHRP-6, GHRP-2, or LHRH.
authors.affiliation: Institute of Biochemistry/Center for Preventive Doping Research, German Sport University Cologne, Cologne, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Thomas
authors.affiliation: Institute of Biochemistry/Center for Preventive Doping Research, German Sport University Cologne, Cologne, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Görgens
authors.affiliation: Institute of Biochemistry/Center for Preventive Doping Research, German Sport University Cologne, Cologne, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Guddat
authors.affiliation: Institute of Doping Analysis and Sports Biochemistry (IDAS) Dresden, Germany.
authors.forename: Detlef
authors.initials: D
authors.lastname: Thieme
authors.affiliation: Nephrology Center Karlstrasse, Düsseldorf, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Dellanna
authors.affiliation: Institute of Biochemistry/Center for Preventive Doping Research, German Sport University Cologne, Cologne, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Schänzer
authors.affiliation: Institute of Biochemistry/Center for Preventive Doping Research, German Sport University Cologne, Cologne, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Thevis
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D004300:Doping in Sports; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D010455:Peptides / Q000737:chemistry* / Q000652:urine; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D010455:Peptides
keywords: Doping control; High-resolution mass spectrometry; Peptide analysis