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1.
J Anal Toxicol ; 31(2): 114-8, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17536748

ABSTRACT

A method for clenbuterol determination in hair has been developed. Hair specimens collected from two calves were decontaminated using hot water followed by methylene chloride. Hair was cut into small pieces, and 100 mg was incubated in 1 mL 0.1M hydrochloric acid overnight at 45 degrees C in the presence of 1 ng acebutolol used as internal standard. After neutralization with 1 mL 0.1M NaOH, 2 mL of bicarbonate buffer (pH 8.6) were added and the preparation was then purified using solid-phase extraction with an Isolute C18 column. Methanolic eluent was evaporated to dryness and the residue was reconstituted with 50 microL methanol. A 5-microL portion was injected onto an ACQUITY UPLC BEH C18 column (2.1 x 50 mm, 1.7 microm) and separation was achieved using a gradient of acetonitrile and formate buffer delivered at a flow rate of 0.6 mL/min. Detection was done on a Waters Micromass Quattro Micro API triple-quadrupole mass spectrometer. Ionization was achieved using electrospray in positive mode. Clenbuterol was identified by two transitions (m/z 277.1 > 203.2 and m/z 277.1 > 132.1). Quantitation was performed with the most intensive transition (m/z 277.1 > 203.2) versus the internal standard monitored using the transition (m/z 337.3 > 116.1). When compared with gas chromatography methods that are generally used for the determination of beta-adrenergics, the major advantages of this method were the sensitivity, a shorter run time, and the absence of a derivatization step. The analysis of two hair samples from calves suspected of drug administration showed low clenbuterol concentrations at 3.6 and 4.8 pg/mg.


Subject(s)
Anabolic Agents/analysis , Bronchodilator Agents/analysis , Clenbuterol/analysis , Fraud , Hair/chemistry , Substance Abuse Detection/veterinary , Animals , Cattle , Forensic Medicine/methods , Spectrometry, Mass, Electrospray Ionization/methods , Spectrometry, Mass, Electrospray Ionization/veterinary , Substance Abuse Detection/methods
2.
J Chromatogr B Analyt Technol Biomed Life Sci ; 836(1-2): 124-8, 2006 May 19.
Article in English | MEDLINE | ID: mdl-16597518

ABSTRACT

A sensitive, specific and reproducible method for the quantitative determination of the anabolic metandienone in human hair has been developed. The preparation involved a decontamination step with methylene chloride. The hair sample (about 50 mg) was solubilised in 1 ml 1 M NaOH, 10 min at 95 degrees C, in presence of 2 ng of nandrolone-d(3) used as internal standard. The homogenate was neutralized and extracted using consecutively a solid-phase extraction (Isolute C(18) eluted with methanol) and a liquid-liquid extraction with pentane. The residue was derivatized by adding 5 microl MSTFA/NH(4)I/2-mercaptoethanol (250 microl; 5 mg; 15 microl) and 45 microl MSTFA, then incubated for 20 min at 60 degrees C. A 1 microl aliquot of derivatized extract was injected into the column (HP5-MS capillary column, 5% phenyl-95% methylsiloxane, 30 m x 0.32 mm i.d., 0.25 microm film thickness) of a Hewlett Packard (Palo Alto, CA, USA) gas chromatograph (6890 Series). Metandienone was identified using three transitions (its daughter ions at m/z 339 and 206 for the parent 444 and 191 for 206) using a Waters Quattro Micro MS-MS system. The transition m/z 444 to 206 has been used as quantification transition and the others as identification transitions. The assay was capable of detecting 2 pg/mg of metandienone when approximately 50 mg of hair material was processed. Linearity was observed for metandienone concentrations ranging from 2 to 500 pg/mg with a correlation coefficient of 0.9997. Intra-day and between-day precisions at 50 pg/mg were 13.4-16.5% and 22.0%, respectively, with an extraction recovery of 48%. The analysis of hair, cut into four segments, obtained from an athlete, revealed the presence of metandienone at the concentrations of 78, 7, 10 and 108 pg/mg in each segment of hair (0-1, 1-2, 2-3 and 3 cm to the tip).


Subject(s)
Anabolic Agents/analysis , Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Hair/chemistry , Methandrostenolone/analysis , Humans , Reference Standards , Reproducibility of Results
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