The liquid chromatography-tandem mass spectrometry method (LC-MS/MS) was developed and validated to detect androgenic steroids: trenbolone, nortestosterone, boldenone, methylboldenone, testosterone, methyltestosterone, 17β-1-testosterone and their metabolites in bovine urine. Sample preparation before LC-MS/MS analysis involved an enzymatic hydrolysis with glucuronidase AS-HP, isolation of free hormones from urine on C(18) SPE column and purification of the extract using liquid-liquid extraction with n-pentane and SPE NH(2) column. For the chromatographic separation of steroids, the Poroshell 120-EC C18 column (150 × 2.1 mm, 2.7 μm) was used. Mass spectrometric measurement was achieved using the API 4000 triple quadrupole (QqQ) instrument with a TurboIon-Spray source operating in positive electrospray ionization mode. The procedure was validated according to the Decision 2002/657/EC. Recovery ranged from 76.5% to 118.9% for all examined compounds. The repeatability was below 20% and reproducibility did not exceed the 25%. The linearity was good for all analytes in the whole range of tested concentrations, as proved by the correlation coefficients greater than 0.99. The decision limit (CCα) ranged from 0.10 to 0.17 μg L(-1) for all analytes, whereas the detection capability (CCβ) ranged from 0.17 to 0.29 μg L(-1). The application of an innovative Poroshell column allowed for very good chromatographic separation of steroids with a much shorter time of analysis.

An LC-MS/MS method was developed for the sensitive and selective determination of zeranol, taleranol, zearalanone, α-zearalenol, β-zearalenol and zearalenone in animal urine. Analysis was performed on the free compounds after enzymatic deconjugation. Sample preparation included liquid-liquid extraction followed by solid-phase extraction (SPE) with C18 and NH2 columns. For chromatographic separation of hormones an Inertsil(®) ODS-3 analytical column (150 mm × 2.1 mm, 3 µm) was used. The analytes were determined and identified by LC-MS/MS on a QTRAP5500 instrument with a TurboIon-Spray source operating in negative electrospray ionisation mode. For confirmatory purposes at least two transitions were obtained for each analyte. According to Commission Decision 2002 /657/EC the validation parameters - recovery, repeatability, reproducibility, linearity, specificity, decision limits and detection capabilities - were determined. All parameters were in agreement with 2002/657/EC performance criteria. The apparent recovery ranged from 76.2% to 116.3% for all examined compounds. The repeatability was below 20% and reproducibility did not exceed the limit of 25% for most analytes. Linearity was good for all analytes in the whole range of tested concentrations, as proved by the correlation coefficients greater than 0.99. The decision limits (CCα) ranged from 0.04 to 0.18 μg l(-1) for all analytes whereas the detection capabilities (CCβ) ranged from 0.07 to 0.31 μg l(-1), respectively. All CCα and CCβ values were below the recommended concentration of 2 μg l(-1). This analytical method will be used in an integrated system for Polish monitoring programmes for the confirmation of violative screened samples.

IntroductionIn the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level.Material and Methods17β-testosterone and internal standards of 17%-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC.ResultsThe method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L−1 and 0.09 μg L−1 respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application.ConclusionsThe developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.

In accordance with Commission Decision 2002/657/EC, confirmatory methods for the detection of prohibited substances should comply with specific requirements, including the criteria for confirmation. Two strategies: multiple reaction monitoring (MRM) and enhanced product ion (EPI) scanning functions were compared for confirming the anabolic compounds from synthetic stilbenes group in bovine urine samples. In the research, twenty samples fortified at the Recommended Concentration (RC) of 1 µg L−1 with diethylstilbestrol, dienestrol and hexestrol were analyzed by liquid chromatography-tandem mass spectrometry on a QTRAP 5500 instrument. The analytical procedure, validated in accordance with the Commission Decision 2002/657/EC, used in the official control of hormones in Poland was applied. The validation parameters were in agreement with 2002/657/EC performance criteria. The effectiveness of MRM and EPI scanning modes for confirmation purposes was evaluated based on the percentage of the results confirmed. In all urine samples recorded in the MRM mode, the confirmation criteria (retention time, relative intensities between transitions) have been fulfilled. The presence of stilbenes in all urine samples using EPI scan mode was confirmed too as evidenced by a good matching of stilbenes spectra in the samples to the reference spectra with critical match factor above 0.7. The results of the research show that EPI scanning function provides the same effectiveness for confirmation of banned compounds as the mostly used MRM scan mode and can be an additional tool to confirm the doubtful case results in the analysis of hormones residues, even at such low concentration levels.

No abstract