title: Simultaneous detection and comparative pharmacokinetics of amoxicillin, clavulanic acid and prednisolone in cows' milk by UPLC-MS/MS.
abstract: Amoxicillin (AMOX), clavulanic acid (CLAV) and prednisolone (PSL) are widely used in combination for the treatment of mastitis in lactating dairy cows. However, no method has been reported to detect these three chemicals in milk in a single assay. In the present work, a reliable and sensitive UPLC-MS/MS method was developed and validated for simultaneous determination of AMOX, CLAV and PSL in cow's milk. The analytes were determined by a positive and negative ionization electrospray mass spectrometer via multiple reaction monitoring. The linear ranges of AMOX, CLAV and PSL were from 2 to 1000ng/mL, 20-1000ng/mL and 1-1000ng/mL, respectively, with the correlation coefficients greater than 0.999. The limits of quantification (LOQs) were 2ng/mL (AMOX), 20ng/mL (CLAV) and 1ng/mL (PSL). Recoveries of the analytes of interest in milk samples were in the ranges of 84.2-101.4%. The intra-day and inter-day precisions ranged from 1.8% to 11.9%. This method was successfully applied to investigate the pharmacokinetics of AMOX, CLAV and PSL in milk from healthy and mastitic cows. The elimination times of AMOX and PSL in mastitic cows were longer than that in healthy cows, but the elimination times of CLAV did not show significant difference.
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, 27708 NC, USA.
authors.forename: Kui
authors.initials: K
authors.lastname: Zhu
authors.affiliation: Animal Husbandry Technology Promotion Station, Yanqing County, Beijing 102100, China.
authors.forename: Jianfen
authors.initials: J
authors.lastname: Wang
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Huang
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
authors.forename: Guanlin
authors.initials: G
authors.lastname: Wang
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
authors.forename: Congying
authors.initials: C
authors.lastname: Li
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. Electronic address: caojie010@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Cao
authors.affiliation: National Reference Laboratory for Veterinary Drug Residues, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China. Electronic address: ding_sy@126.com.
authors.forename: Shuangyang
authors.initials: S
authors.lastname: Ding
mesh_terms: D000658:Amoxicillin / Q000493:pharmacokinetics*; D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods*; D019818:Clavulanic Acid / Q000493:pharmacokinetics*; D005260:Female; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry*; D011239:Prednisolone / Q000493:pharmacokinetics*; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D019818:Clavulanic Acid; D000658:Amoxicillin; D011239:Prednisolone
keywords: Amoxicillin; Clavulanic acid; Comparative pharmacokinetics; Prednisolone; UPLC–MS/MS