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1.
Lab Hematol ; 13(2): 43-8, 2007.
Article in English | MEDLINE | ID: mdl-17573280

ABSTRACT

The Sysmex R-500 (R-500) Hematology Analyzer is a bench-top system appropriate for the analysis of limited batches of blood samples. The R-500 provides percentage proportional (RET%), absolute reticulocyte (RET#), and absolute red blood cell (RBC#) counts. The system was validated at the Doping Control Laboratory of Athens, according to the International Committee for Standardization in Hematology, International Standards Organization (ISO/IEC) 17025, and World Antidoping Agency (WADA) specifications. The instrument calibration was performed according to the manufacturer and validation parameters comprised linearity, precision, uncertainty (intermediate and long-term precision), comparability, effect of drift, carryover, stability, and accuracy. The linearity and the comparability studies for RET#, RET%, and RBC# were expressed in regression factors (R2) and coefficients of correlation [r(x, y)], respectively. For the precision studies, the coefficients of variation for RET#, RET%, and RBC# were 9.49%, 9.83%, and <1.5%, respectively. For the intermediate precision studies, the coefficients of variation for RET#, RET%, and RBC# were 3.1%, 3.6%, and 0.6%, respectively. Carryover was found to be negligible. Sample stability was demonstrated at both room temperature and at 4 degrees C over a 24-hour period. Comparability studies for the R-500 were performed using a Sysmex SE-9500. The total evaluation led to the conclusion that the R-500 is an accurate and precise analyzer and because of to its relatively limited size, it can be considered a portable instrument, capable to be used in sports competition and training sites, where doping control and health tests are conducted. The analytical methodology of RET% measurement by the R-500 has been incorporated into the Doping Control Laboratory of Athens' Scope of Accreditation according to the ISO/IEC 17025 and WADA specifications.


Subject(s)
Doping in Sports , Reticulocyte Count/instrumentation , Adult , Cold Temperature , Equipment Design , Humans , Reproducibility of Results , Reticulocyte Count/standards , Reticulocytes/ultrastructure , Temperature
2.
Anal Chim Acta ; 573-574: 242-9, 2006 Jul 28.
Article in English | MEDLINE | ID: mdl-17723530

ABSTRACT

A new liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) (n) ion trap method for the determination of corticosteroids in urine has been developed and validated. Some anabolic agents, such as epitrenbolone, trenbolone, 2-hydroxymethylformebolone, tetrahydrogestrinone, gestrinone and formoterol were included in the LC-ESI-MS method. Matrix interference, specificity, identification capability, carry over and robustness were estimated as validation parameters. Recoveries ranged from 74 to 113% at the minimum required performance limit (MRPL), which is 30 ng mL(-1) for corticosteroids and 10 ng mL(-1) for anabolic agents. Methods for the confirmation and quantification of norpseudoephedrine, ephedrine, methylephedrine, salbutamol, morphine and morphine glucuronide were also developed and validated and in order to minimize analysis time, direct urine injection was used. These methods proved to be specific, accurate and precise across a calibration range for each substance since matrix interference, specificity, carry over, within and between run precision, limit of detection, limit of quantification, intermediate precision and uncertainty were estimated.

3.
J Pharm Biomed Anal ; 35(1): 107-16, 2004 Apr 01.
Article in English | MEDLINE | ID: mdl-15030885

ABSTRACT

Xylazine and its main metabolites were detected in equine urine after a single-dose intravenous administration of 0.98 and 1.01 mg/kg body weight xylazine, respectively, in two horses, in order to be used for equine doping control routine analysis. The urine levels of the parent drug and its metabolites were determined using gas chromatography-mass spectrometry (GC-MS). Xylazine is metabolised rapidly, down to a concentration level of about 1.0 microg/ml after 1-3h administration. Seven metabolites were identified in urine. 4-Hydroxy-xylazine, the major metabolite, could be traced for 25 h and it is regarded as the long-term metabolite of xylazine in horse. 2,6-Dimethylaniline was, for the first time, reported as metabolite in equine.


Subject(s)
Adrenergic alpha-Agonists/urine , Doping in Sports , Horses/urine , Xylazine/urine , Adrenergic alpha-Agonists/metabolism , Animals , Female , Gas Chromatography-Mass Spectrometry , Injections, Intravenous , Molecular Structure , Xylazine/metabolism
4.
Rapid Commun Mass Spectrom ; 15(19): 1796-801, 2001.
Article in English | MEDLINE | ID: mdl-11565096

ABSTRACT

A study of excretion in human urine of ecdysterone, which is the active component of several over-the-counter supplements such as "Ecdysten", reportedly used by athletes, is presented. The study was performed after oral administration of 20 mg of ecdysterone. The collected urine samples were prepared using the standard screening extraction procedure for the free and conjugated fraction of anabolic steroids, and analyzed by gas chromatography (GC) coupled with quadrupole mass spectrometry (MS) and also with high-resolution mass spectrometry (HRMS). Two ecdysterone metabolites were identified and detected along with unchanged ecdysterone. Accurate mass measurements were made for diagnostic ions, including the molecular ion of the main metabolite of ecdysterone, deoxyecdysone, which, to our knowledge, has not previously been reported in the literature. These accurate mass measurements support the proposed fragmentation scheme.


Subject(s)
Ecdysterone/urine , Administration, Oral , Ecdysterone/administration & dosage , Ecdysterone/pharmacokinetics , Gas Chromatography-Mass Spectrometry , Humans , Mass Spectrometry
5.
J Chromatogr B Biomed Sci Appl ; 758(2): 311-4, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11486842

ABSTRACT

A selective gas-liquid chromatographic method with mass spectrometry (GC-MS) for the simultaneous confirmation and quantification of ephedrine, pseudo-ephedrine, nor-ephedrine, nor-pseudoephedrine, which are pairs of diastereoisomeric sympathomimetic amines, and methyl-ephedrine was developed for doping control analysis in urine samples. O-Trimethylsilylated and N-mono-trifluoroacetylated derivatives of ephedrines--one derivative was formed for each ephedrine--were prepared and analyzed by GC-MS, after alkaline extraction of urine and evaporation of the organic phase, using d3-ephedrine as internal standard. Calibration curves, with r2>0.98, ranged from 3.0 to 50 microg/ml depending on the analyte. Validation data (specificity, % RSD, accuracy, and recovery) are also presented.


Subject(s)
Ephedrine/urine , Gas Chromatography-Mass Spectrometry/methods , Calibration , Reference Standards , Reproducibility of Results
6.
Talanta ; 55(6): 1173-80, 2001 Dec 24.
Article in English | MEDLINE | ID: mdl-18968470

ABSTRACT

Flurbiprofen and its main acidic metabolites were detected in equine urine after a single-dose administration of 500 mg flurbiprofen to two 2.5-3.5-years-old mares, in order to be used in equine doping control routine analysis. The urine levels of the parent drug were determined using GC/MS. Five acidic metabolites were found in the urine. The structure of the proposed metabolites was confirmed by HRMS accurate mass measurements. The highest flurbiprofen concentration was 204 mug ml(-1) at 1-3 h post administration. Flurbiprofen could be detected for 24-37 h in urine using the standard screening procedure. All metabolites were present 25 h post administration, while 4'-hydroxyflurbiprofen could be traced for more than 48 h and it is regarded as the long-term metabolite of flurbiprofen in horse.

7.
J Chromatogr B Biomed Sci Appl ; 726(1-2): 141-8, 1999 Apr 16.
Article in English | MEDLINE | ID: mdl-10348180

ABSTRACT

An excretion study of the beta2-agonist 7-[3-[(beta-3,5-trihydroxyphenethyl)amino]-propyl]theophylline (reproterol) in human urine, which is reportedly misused by athletes and horses as a doping agent, is presented. The study was performed after an oral administration of 20 mg of reproterol hydrochloride. The collected urine samples were prepared using the standard anabolic steroid extraction procedure and analyzed by gas chromatography coupled with quadrupole mass spectrometry and, also, with high-resolution mass spectrometry (HRMS). The main reproterol metabolite was found, whereas unchanged reproterol was not detected. The structure of the main metabolite was confirmed by an accurate HRMS measurement of diagnostic ions. Finally, an excretion urine profile of the main metabolite is presented. The mass spectrum of another possible unidentified reproterol metabolite is also reported.


Subject(s)
Adrenergic beta-Agonists/urine , Metaproterenol/analogs & derivatives , Theophylline/analogs & derivatives , Adrenergic beta-2 Receptor Agonists , Doping in Sports , Drug Combinations , Gas Chromatography-Mass Spectrometry , Humans , Metaproterenol/urine , Theophylline/urine
8.
J Chromatogr B Biomed Sci Appl ; 724(2): 205-12, 1999 Mar 19.
Article in English | MEDLINE | ID: mdl-10219660

ABSTRACT

A simple, rapid and sensitive reversed-phase ion-pair high-performance liquid chromatographic method for the determination of N-acetylneuraminic acid and 2-deoxy-2,3-dehydro-N-acetylneuraminic acid in biological fluids is described. Determination of N-acetylneuraminic acid released by acidic hydrolysis, in serum, urine and saliva, and 2-deoxy-2,3-dehydro-N-acetylneuraminic acid in urine, without hydrolysis, was accomplished by injecting the sample without derivatization, into the chromatograph. Measurements were carried out isocratically within 6 min using a C18 column and a mobile phase of aqueous solution of triisopropanolamine, as ion-pair reagent, 60 mM, pH 3.5 at room temperature with UV absorbance detection. The present method is reported for the first time for the determination of sialic acids in biological fluids. Recoveries in serum, urine and saliva ranged from 90 to 102% and the limits of detection were 60 nM and 20 nM for the two sialic acids, respectively. The method has been applied to normal and pathological sera from patients with breast, stomach, colon, ovarian and cervix cancers, to normal urine and urine from patient with sialuria and to normal saliva.


Subject(s)
Chromatography, High Pressure Liquid/methods , Saliva/chemistry , Sialic Acids/metabolism , Case-Control Studies , Female , Humans , Male , Neoplasms/blood , Neoplasms/metabolism , Neoplasms/urine , Reproducibility of Results , Sialic Acids/blood , Sialic Acids/urine , Spectrophotometry, Ultraviolet
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