Abstract
The presence of proteolytic enzymes in urine samples, coming from exogenous or endogenous sources, enhances the cleavage of human chorionic gonadotropin (hCG). Moreover, elevated temperatures occurring occasionally during the delayed transportation of sport urine samples, favor the nicking of the hCG molecule. The aim of the current study, funded by the World Anti-Doping Agency (WADA), was the application of a stabilization mixture in athletes' urine samples to chemically inactivate proteolytic enzymes coming from exogenous or endogenous sources so as to prevent the degradation of hCG. The stabilization mixture applied, already tested for the stabilization of endogenous steroids and recombinant erythropoietin (rEPO), was a combination of antibiotics, antimycotic substances, and protease inhibitors. Incubation experiments were conducted in the presence or absence of the stabilization mixture in urine aliquots spiked with six proteases (first series of experiments) and one microorganism associated with urinary tract infections (UTI) (second series of experiments). Intact hCG levels were evaluated by using the EIAgen Total hCG kit. In the first series of experiments, hCG levels were reduced in the untreated aliquots following incu...Continue Reading
References
Feb 15, 1992·Experientia·M R Maurizi
Aug 1, 1995·Prenatal Diagnosis·U Sancken, D Bahner
Oct 1, 1994·Endocrine Reviews·J F O'ConnorR E Canfield
Jan 1, 2003·Clinical Chemistry·Steven BirkenUlf-Håkan Stenman
Mar 16, 2004·Clinical Chemistry·Laurence A ColeGeorge S Cembrowski
Apr 24, 2004·Clinical Chemistry·Ulf-Håkan Stenman
Oct 30, 2004·Clinical Chemistry·Adrian BristowUNKNOWN IFCC Working Group on hCG
May 26, 2007·International Journal of Sports Medicine·M ThevisW Schänzer
Apr 17, 2008·British Journal of Pharmacology·U-H StenmanH Alfthan
Jan 28, 2009·Reproductive Biology and Endocrinology : RB&E·Laurence A Cole
Feb 24, 2009·Analytical Biochemistry·M TsivouC G Georgakopoulos
Feb 24, 2009·Analytical Biochemistry·M TsivouC G Georgakopoulos
Oct 13, 2009·Expert Review of Molecular Diagnostics·Laurence A Cole
Dec 5, 2009·Clinica Chimica Acta; International Journal of Clinical Chemistry·M TsivouC G Georgakopoulos
Feb 1, 2009·Drug Testing and Analysis·Andreas ThomasMario Thevis
Apr 1, 2010·Drug Testing and Analysis·Maxie KohlerMario Thevis
Citations
Apr 19, 2011·Analytical and Bioanalytical Chemistry·Maria TsivouCostas G Georgakopoulos
Sep 6, 2011·Forensic Science International : Synergy·Neil RobinsonMartial Saugy
Jan 31, 2012·Drug Testing and Analysis·Mario ThevisWilhelm Schänzer
Aug 9, 2016·Drug Testing and Analysis·Maria TsivouFrancesco Botrè
Jan 15, 2017·Drug Testing and Analysis·David PalmerRob Howitt
Nov 11, 2014·Expert Review of Proteomics·Mario ThevisWilhelm Schänzer