SHORT_COMMUNICATION This study provides insight into the development and validation of the simple, rapid and sensitive method of Liquid Chromatography-Tandem Mass Spectrometry for determining the residues of dexamethasone in bovine milk. The maximum residue limit for dexamethasone in bovine milk is 0.3 ng/ml-1. Chromatographic separation was achieved on an Agilent Proshell 120 SB:C18 (2.7μm 100x3.0 mm) column. The bovine milk was extracted with ethyl acetate, and the evaporated elution was dissolved with hexane, water and methanol, and analyzed by the LC-MS/MS method. The mobile phase A was a solution of 5 Mm ammonium formate in water, while the mobile phase B was 0.1% formic acid in acetonitrile. The calibration graphics were prepared within the range of 0.15–0.6 ng/ml−1, and a successful linearity was achieved (r ≥0.999). The limit of detection was 0.016 ng/ml−1. The decision limit (CCα) and detection capability (CCβ) were 0.34 and 0.38 ng/ml−1, respectively. https://macvetrev.mk/Files/Article/2020/10.2478/macvetrev-2020-0014/macvetrev-2020-0014.pdf 2020-03-15T09:00:00 69 73 10.2478/macvetrev-2020-0014 dexamethasone LC-MS/MS milk Mehmet Nihat Ural nihatural@yahoo.com false 1 Laboratory of Residue, Department of Pharmacology, Pendik Veterinary Control Institute, Bati Mah. Yunus Cad. 2/1, 34890 Pendik, Istanbul, Turkey LEAD_AUTHOR Arzu Kotan false 2 Laboratory of Residue, Department of Pharmacology, Pendik Veterinary Control Institute, Bati Mah. Yunus Cad. 2/1, 34890 Pendik, Istanbul, Turkey AUTHOR Cherlet, M,. De Baere, S., De Backer, P.J. (2004). Quantitative determination of dexamethasone in bovine milk by liquid chromatography-atmospheric pressure chemical ionizationtandem mass spectrometry. J Chromatogr B. 805(1): 57-65. 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