‘Wrong-way-round ionization’ and screening for doping substances in human urine by high-performance liquid chromatography/orbitrap mass spectrometry
Moscow Antidoping Center, 105005, Moscow, Elizavetynsky10. Journal of Mass Spectrometry
(Impact Factor: 2.38).
03/2012; 47(3):381-91. DOI: 10.1002/jms.2055
To free analytical resources for new classes of doping substances, such as banned proteins, maximization of the number of compounds that can be determined with high sensitivity in a single run is highly urgent. This study demonstrates an application of 'wrong-way-round ionization' for the simultaneous detection of multiple classes of doping substances without the need to switch the polarity. A screening method for the detection of 137 compounds from various classes of prohibited substances (stimulants, diuretics, β(2)-agonists, β-blockers, antiestrogens, glucocorticosteroids and anabolic agents) has been developed. The method involves an enzymatic hydrolysis, liquid-liquid extraction and detection by liquid chromatography/orbitrap mass spectrometry with wrong-way-round ionization. Up to 64% of compounds had a 10-fold lower limit of detection (LOD) than the minimum required performance limit. To compare the efficiency of conventional ionization relative to wrong-way-round ionization of doping substances in + ESI, a fortified blank urine sample at the minimum required performance limit was analyzed using two ESI approaches. All compounds were detected with markedly better S/N in a high-pH mobile phase, with the exception of acetazolamide (minimal change in S/N, < 20%).The method was validated by spiking 10 different blank urine samples at five different concentrations. Validation parameters included the LOD, selectivity, ion suppression, extraction recovery and repeatability.
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- " This method describes simultaneous analysis of lamotrigine, phenobarbital , 10-OH-carbazepine, phenytoin and carbamazepine, but does not cover newer AEDs, for example levetiracetam, pregabalin or gabapentin. Several papers report a higher analytical response for basic pH mobile phases as compared to acidic,         and an evaluation of the analytical response for carbamazepine using different alkaline mobile phases, concluded with pH 7.9 as favourable.  Our method was therefore developed and validated using a mildly alkaline mobile phase with pH of 7.9. "
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Drug Testing and Analysis 10/2014; 7(7). DOI:10.1002/dta.1733 · 2.51 Impact Factor
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ABSTRACT: The timely update of the list of prohibited substances and methods of doping (as issued by the World Anti-Doping Agency) is an essential aspect of international anti-doping efforts and represents consensual agreement by expert panels regarding substances and the methods of performance manipulation in sports. The annual banned-substance review for human doping controls critically summarizes recent innovations in analytical approaches; its purpose is to improve the quality of doping controls by reporting emerging and advancing methods that focus on detecting known and recently outlawed substances. This review surveys new and/or enhanced procedures and techniques of doping analysis together with information relevant to doping control that has been published in the literature between October 2009 and September 2010.
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Available from: onlinelibrary.wiley.com
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ABSTRACT: International anti-doping efforts are harmonized and regulated under the umbrella of the World Anti-Doping Code and the corresponding Prohibited List, issued annually by the World Anti-Doping Agency (WADA). The necessity for a frequent and timely update of the Prohibited List (as the result of a comprehensive consultation process and subsequent consensual agreement by expert panels regarding substances and methods of performance manipulation in sports) is due to the constantly growing market of emerging therapeutics and thus new options for cheating athletes to illicitly enhance performance. In addition, 'tailor-made' substances arguably designed to undermine sports drug testing procedures are considered and the potential of established drugs to represent a doping substance is revisited in light of recently generated information. The purpose of the annual banned substance review is to support doping controls by reporting emerging and advancing methods dedicated to the detection of known and recently outlawed substances. This review surveys new and/or enhanced procedures and techniques of doping analysis together with information relevant to doping controls that has been published in the literature between October 2010 and September 2011.
Drug Testing and Analysis 01/2012; 4(1):2-16. DOI:10.1002/dta.415 · 2.51 Impact Factor
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