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1

Determination of 17beta-oestradiol and testosterone in bovine serum with gas chromatography-mass spectrometry

100%
Wozniak B., Matraszek-Zuchowska I., Zmudzki J.
Bulletin of the Veterinary Institute in Puławy
|
2011
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tom 55
|
nr 4
A simple and sensitive method was developed for determination of 17β-oestradiol and testosterone in bovine serum. The hormones were analysed and quantified as heptafluorobutyric anhydride derivatives by gas chromatography-mass spectrometry after extraction from serum without any cleanup step. The method was validated according to the requirements listed in the Commission Decision 2002/657/EC. Decision limit (CCα) and detection capability (CCβ) were based on the detection of the most abundant ion and the values: 0.011 µg L⁻¹ and 0.018 µg L⁻¹ for 17β-oestradiol were obtained, respectively . The repeatability for the validation level 0.040 µg L⁻¹ was 19.2% and within laboratory reproducibility - 25.8%. For testosterone, CCα and CCβ were 0.056 µg L⁻¹ and 0.096 µg L⁻¹ alternately with repeatability and reproducibility below 12%. The values of the detection limits of 17β-oestradiol and testosterone were found to be below the recommended concentration, set at 0.1 µg L⁻¹ and 0.5 µg L⁻¹, respectively. The method was successfully applied in the official control of hormone residues in Poland.
2

Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum

100%
Wozniak B., Matraszek-Zuchowska I., Witek S., Posyniak A.
Journal of Veterinary Research
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2017
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tom 61
|
nr 1
3

Determination of zeranol and its metabolites in bovine muscle tissue with gas chromatography-mass spectrometry

100%
Matraszek-Zuchowska I., Wozniak B., Zmudzki J.
Bulletin of the Veterinary Institute in Puławy
|
2012
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tom 56
|
nr 3
This paper describes the quantitative method of determination of chosen substances from resorcylic acid lactones group: zeranol, taleranol, α-zearalenol, ß-zearalenol, and zearalanone in bovine muscle tissue. The presented method is based on double diethyl ether liquid-liquid extraction (LLE), solid phase extraction (SPE) clean up, and gas chromatography mass spectrometry (GC- MS) analysis. The residues were derivatised with a mixture of N-methyl-N-trimethylsilyltrifluoroacetamide, ammonium iodide, and DL-dithiothreitol (1,000:2:5, v/w/w). The GC-MS apparatus was operated in positive electron ionisation mode. The method was validated according to the European Union performance criteria pointed in Decision Commission 2002/657/EC. The average recoveries of all analytes at 1 µg kg⁻¹ level were located between 83.7% and 94.5% values with the coefficients of variation values <25%. The decision limits (CCα) and detection capabilities (CCß) for all analytes ranged from 0.58 to 0.82 µg kg⁻¹ and from 0.64 to 0.94 µg kg⁻¹, respectively. The procedure has been accredited and is used as a screening and confirmatory method in control of hormone residues in animal tissues.
4

Determination of the thyreostats in animal feeding stuffs using liquid chromatography - tandem mass spectrometry

100%
Wozniak B., Witek S., Matraszek-Zuchowska I., Zmudzki J.
Bulletin of the Veterinary Institute in Puławy
|
2014
|
tom 58
|
nr 3
A rapid liquid chromatography tandem mass spectrometry method was developed and validated to detect and confirm five thyreostatic drugs: tapazole, thiouracil, methylthiouracil, propylthiouracil, and phenylthiouracil in animal feeding stuff samples. Thyreostats were extracted from feed with methanol, and then degreasing of the extract with petroleum ether was performed, followed by the derivatisation of the compounds with 3-iodobenzylbromide in basic medium (pH 8.0). The derivatives were extracted with diethyl ether and analysed by gradient elution on a Poroshell 120-EC C18 column with triple quadrupole MS detection with turbo spray source in positive ionisation mode. The method was validated in accordance with the Commission Decision 2002/657/EC. For validation level of 10 µg kg⁻¹, the recoven ranged from 82% to 97.5% for all examined compounds. The repeatability and reproducibility did not exceed the limit of 20% for all analytes. The linearity was good for all thyreostats in the whole range of tested concentrations, as proved by the correlation coefficients greater than 0.99. The decision limits (CCα) ranged from 1.63 µg kg⁻¹ to 3.95 µg kg⁻¹, whereas the detection capabilities (CCß) ranged from 2.74 µg kg⁻¹ to 6.73 µg kg⁻¹. The developed analysis is sensitive and robust, and therefore useful for quantification and confirmation of thyreostats in residue control programme.
5

Determination of steroid esters in hair of slaughter animals by liquid chromatography with tandem mass spectrometry

100%
Matraszek-Zuchowska I., Wozniak B., Sielska K., Posyniak A.
Journal of Veterinary Research
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2019
|
tom 63
|
nr 4
6

Levels of the natural hormones 17 Beta - oestradiol and testosterone in serum of cattle: results from population studies in Poland

88%
Wozniak B., Witek S., Matraszek-Zuchowska I., Klopot A., Posyniak A.
Journal of Veterinary Research
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2016
|
tom 60
|
nr 4
7

Evaluation of the effect of surgical and immunological castration of male pigs on boar taint compounds in oral fluid and fat tissue by LC-MS/MS method

88%
Wozniak B., Cybulski P., Jablonski A., Witek S., Matraszek-Zuchowska I.
Journal of Veterinary Research
|
2020
|
tom 64
|
nr 4
8

Determination of natural and synthetic oestrogens in surface water using gas chromatography-mass spectrometry

88%
Wozniak B., Klopot A., Matraszek-Zuchowska I., Sielska K., Zmudzki J.
Bulletin of the Veterinary Institute in Puławy
|
2014
|
tom 58
|
nr 4
A simple and sensitive gas chromatography method was developed to determine a group of oestrogens in surface water. In the first stage of analysis, enzymatic hydrolysis of oestrogen metabolites with glucuronidase AS-HP was performed. Free compounds were extracted from 200 mL of water sample on C18 SPE column (6 mL, 1000 mg). The evaporated extract was subjected to derivatisation with a mixture of MSTFA/NH4I/DTT (1000:2:5, v/w/w). The separation of the analytes on HP-5ms capillary column was conducted. The method was validated according to the Commission Decision 2002/657/EC. Recoven in spiked samples ranged from 90% to 120 % with standard deviation lower than 30% for all examined compounds. The decision limit and detection capability of five oestrogens were in the range of 0.3-0.6 ng L⁻¹ and 0.5-0.9 ng L⁻¹, respectively. Nineteen water samples collected from different sites of several Polish rivers and lakes were tested for the presence of oestrogens. Some target compounds such as 17α-oestradiol, l7ß-oestradiol, oestrone, oestriol, and 17α-ethynyloestradiol were found in trace amounts in the analysed samples. The highest concentration observed for oestradiol reached 23 ng L⁻¹.
9

Screening and confirmatory GC-MS methods for the detection of trenbolone in bovine urine

88%
Wozniak B., Matraszek-Zuchowska I., Semeniuk S., Klopot A., Zmudzki J.
Bulletin of the Veterinary Institute in Puławy
|
2013
|
tom 57
|
nr 4
Sensitive and selective methods for the screening (GC-MS) and confirmatory analysis (GC-MS/MS) of 17α- and 17ß- trenbolone in bovine urine were developed. In the first stage of the analysis, the enzymatic hydrolysis of trenbolone metabolites with glucuronidase AS-HP in acetate buffer (pH 5.2) solution was carried out. Free compounds were extracted from urine with diethyl ether. For the purification of the extract solid phase, extraction with C18 and NH2 columns was applied. The evaporated extract was subjected to two derivatisation steps; the first with MSTFA/12 solution and second with MSTFA. The separation of the analytes on HP-5 ms capillary column was conducted, llie methods were validated according to the Commission Decision 2002/657/EC. For GC-MS method, CCα and CCß were 0.21-0.36 µg L⁻¹ for 17α- trenbolone and 0.20-0.34 µg L⁻¹ for 17β- trenbolone, while for GC-MS/MS method the values were lower and amounted to 0.15-0.25 µg L⁻¹ for 17α- trenbolone and 0.20-0.34 µg L⁻¹ for 17ß-trenbolone. Method recoveries in spiked samples ranged from 86%-111% with standard deviation lower than 25% for both detection techniques.
10

Control of anabolic hormone residues in tissues of slaughter animals in Poland during the period of 2011–2015

76%
Matraszek-Zuchowska I., Wozniak B., Klopot A., Witek S., Sielska K., Posyniak A.
Journal of Veterinary Research
|
2017
|
tom 61
|
nr 1
11

Control of residues of thyreostats in slaughter animals in Poland in 2011–2017

76%
Wozniak B., Matraszek-Zuchowska I., Sielska K., Witek S., Posyniak A., Niemczuk K., Zmudzki J.
Journal of Veterinary Research
|
2018
|
tom 62
|
nr 4
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