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Kaklamanos G.,Veterinary Laboratory of Serres | Theodoridis G.,Aristotle University of Thessaloniki
Journal of Agricultural and Food Chemistry

A precise and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of dapsone in muscle tissue and milk has been developed. The sample preparation was based on extraction with organic solvent and automated solid-phase extraction (SPE) cleanup. At least three product ions were monitored for the analyte. The method was validated according to the European Decision 2002/657/EC. Estimated analytical limits were 0.0018 ng/g for CCα and 0.0031 ng/g for CCβ in meat and milk. An excellent linear concentration range was observed for both matrices with a correlation coefficient better than 0.997. Recoveries were 105-117% in meat and 101-108% in milk, with satisfactory precision and coefficients of variance (CV) less than 8%. Additionally, a simplified quantification approach was successfully evaluated depending only on the response factor (F) without the use of calibration curve. The developed method provides reliable and sensitive identification and quantification of dapsone in meat and milk. © 2011 American Chemical Society. Source

Kaklamanos G.,Veterinary Laboratory of Serres | Theodoridis G.,Aristotle University of Thessaloniki
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences

A rapid multi-method was developed for the determination of 21 growth promoters from different classes, including gestagens, corticosteroids, RALs, stilbenes, steroids in bovine milk by liquid chromatography-tandem mass spectrometry (LC-MS/MS). All compounds were eluted from the analytical column in less than 8.5. min and were subsequently analyzed with atmospheric pressure chemical ionization (APCI) using both positive and negative mode. Sample preparation included extraction of the compounds with acetonitrile and purification with solid-phase extraction (SPE). The method was validated according to Commission Decision 2002/657/EC, at a validation level of 1. ng/ml. The specificity, accuracy, precision, decision limit (CCα) and the detection capability (CCβ) were satisfactory evaluated. The recoveries ranged from 80.7% to 118.8% and reproducibility represented as coefficient of variance (CV) was from 1.8% to 13.0%. The CCα and CCβ values were in the ranges 0.06-0.10. ng/ml and 0.11-0.17. ng/ml, respectively. The developed method was applied in real samples proving its rapidness and sensitivity for the determination of the 21 growth promoters. © 2013 Elsevier B.V. Source

Merou A.,Aristotle University of Thessaloniki | Kaklamanos G.,Veterinary Laboratory of Serres | Kaklamanos G.,European Commission | Theodoridis G.,Aristotle University of Thessaloniki
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences

A sensitive and robust LC-APCI-MS/MS method has been developed for the unambiguous detection and quantitative determination of the antimicrobial agent Carbadox, its metabolite quinoxaline-2-carboxylic acid and methyl-3-quinoxaline-2-carboxylic acid the major metabolite of Olaquindox. The method was aimed for application in the assaying of muscle tissue so the developed sample preparation scheme subjected samples to enzymatic digestion prior to the application of solid phase extraction clean-up. Subsequently the purified extracts were analyzed by reversed-phase LC-MS/MS in positive APCI and multiple reaction monitoring mode. The method was validated at a level of 1 μg/kg. The decision limits CC α and detection capability CC β ranged from 0.09 μg/kg to 0.24 μg/kg and from 0.12 μg/kg to 0.41 μg/kg, respectively. The accuracy and precision of the method were satisfactory. The recoveries ranged from 92% to 101% for the metabolites and from 60% to 62% for Carbadox, with coefficient of variances (CVs) less than 12%. The developed method proved efficient and straightforward allowing positive identification and quantitation of the target banned analytes and is thus suitable for application in residue control programmes and metabolism studies. © 2011 Elsevier B.V. Source

Kaklamanos G.,Veterinary Laboratory of Serres | Theodoridis G.A.,Aristotle University of Thessaloniki | Dabalis T.,Veterinary Laboratory of Serres | Papadoyannis I.,Aristotle University of Thessaloniki
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences

In the present paper we report the LC-MS/MS determination of residues of 12 anabolic steroids in bovine serum, as an expansion of our work protocols for steroids determination in biological matrices. Steroids analyzed included α-zearalanol, β-zearalanol, α-trenbolone, β-trenbolone, methyltestosterone, α-estradiol, β-estradiol, ethynylestradiol, α-boldenone, β-boldenone, α-nortestosterone and β-nortestosterone. Following protein precipitation, serum samples were cleaned up by solid-phase extraction using Oasis HLB and Amino cartridges. Atmospheric pressure chemical ionization (APCI) in both positive and negative ionization modes was used and mass spectrometry detection was carried out in multiple reaction monitoring mode following two or (in most cases) three product ions per precursor ion. The method was validated in accordance with the Commission Decision 2002/657/EC. The decision limit (CCα) values obtained, ranged from 0.01 to 0.07. ng/ml and the detection capability (CCβ) values obtained ranged from 0.02 to 0.12. ng/ml. The recoveries ranged from 70.2% to 118.2%. The developed method is suitable for routine and confirmatory purposes such as control of illegal use in livestock production. © 2010 Elsevier B.V. Source

Terzopoulou E.,Aristotle University of Thessaloniki | Terzopoulou E.,Veterinary Laboratory of Serres | Voutsa D.,Aristotle University of Thessaloniki | Kaklamanos G.,Veterinary Laboratory of Serres
Environmental Science and Pollution Research

A multi-residue method, based on gas chromatography coupled to tandem mass spectrometry (GC-MS/MS), has been developed for the determination of 70 organic micropollutants from various chemical classes (organochlorinated, organophosphorous, triazines, carbamate and urea, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, pharmaceuticals, phenols, etc.) in surface waters. A single-step SPE extraction using OASIS HLB cartridges was employed for the recovery of target micropollutants. The method has been validated according to monitoring performance criteria of the Water Framework Directive, taking into account the approved guidelines on quality assurance and quality control. The recoveries ranged from 60 to 110 %, the coefficient of variation from 0.84 to 27.4 %, and the uncertainty from 6 to 37 %. The LOD varied from 6.0 to 40 ng/L. The limits of quantification for the priority pollutants anthracene, alachlor, atrazine, benzo(a)pyrene, chlorfenvinphos, diuron, isoproturon, nonylphenol, simazine, and terbutryn fulfill the criterion of <30 % of the relevant environmental standards. The method was employed to investigate the water quality in the basin of a transboundary river, Strymonas, in NE Greece during three sampling campaigns conducted in the year 2013. Thirty-nine compounds were detected in the river water. Metolachlor, diuron, isoproturon, salicylic acid, chlorfenvinphos, 1,2-benzanthracene, pyrene, diflubenzuron, and carbaryl exhibited the highest detection frequencies. © 2014, Springer-Verlag Berlin Heidelberg. Source

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