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Moscow, Russia

Rodin I.A.,Moscow State University | Braun A.V.,Moscow State University | Shpigun O.A.,Moscow State University | Savel'eva E.I.,Scientific Research Institute of Hygiene | And 3 more authors.
Journal of Analytical Chemistry | Year: 2011

An approach to the detection of metabolites of organophosphorous agents (OPA), such as O-isopropylmethylphosphonic acid (detection limit, 4 ng/mL), O-pinacolylmethylphosphonic acid (0.6 ng/mL), and O-isobutylmethylphosphonic acid (1 ng/mL), in plasma samples was developed using liquid chromatography-mass spectrometry. The curves of the elutionxcretion of OPA metabolites were obtained for the samples of biological material of rats exposed to toxic substances. Determination was performed by mass spectrometry with electrospray ionization in the negative ion mode, using deprotonated molecules for detection. The biological samples were analyzed by reversed-phase chromatography using hydrophilic end-capped adsorbents. Solid phase extraction on reversed-phase adsorption cartridges containing a copolymer of styrene and divinylbenzene was proposed for sample preparation. © Pleiades Publishing, Ltd., 2011. Source


Semenistaya E.,Anti Doping Center | Zvereva I.,Anti Doping Center | Thomas A.,German Sport University Cologne | Thevis M.,German Sport University Cologne | And 2 more authors.
Drug Testing and Analysis | Year: 2015

Growth hormone releasing peptides (GHRPs) stimulate secretion of endogenous growth hormone and are listed on the World Anti-Doping Agency (WADA) Prohibited List. To develop an effective method for GHRPs anti-doping control we have investigated metabolites of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin in urine after nasal administration. Each compound was administrated to one volunteer. Samples were collected for 2 days after administration, processed by solid-phase extraction on weak cation exchange cartridges and analyzed by means of nano-liquid chromatography - high resolution mass spectrometry. Six metabolites of GHRP-1 were identified. GHRP-1 in the parent form was not detected. GHRP-1 (2-4) free acid was detected in urine up to 27 h. GHRP-2, GHRP-2 free acid and GHRP-2 (1-3) free acid were detected in urine up to 47 h after administration. GHRP-6 was mostly excreted unchanged and detected in urine 23 h after administration, its metabolites were detectable for 12 h only. Hexarelin and Ipamorelin metabolized intensively and were excreted as a set of parent compounds with metabolites. Hexarelin (1-3) free acid and Ipamorelin (1-4) free acid were detected in urine samples after complete withdrawal of parent substances. GHRPs and their most prominent metabolites were included into routine ultra-pressure liquid chromatography-tandem mass spectrometry procedure. The method was fully validated, calibration curves of targeted analytes were obtained and excretion curves of GHRPs and their metabolites were plotted. Our results confirm that the detection window after GHRPs administration depends on individual metabolism, drug preparation form and the way of administration. © 2015 John Wiley & Sons, Ltd. Source

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