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Xie K.,Yangzhou University | Xie K.,Key Laboratory for Animal Genetic | Guo H.,Yangzhou University | Guo H.,Key Laboratory for Animal Genetic | And 19 more authors.
Journal of Animal and Veterinary Advances | Year: 2012

Eggs of laying hens were used to study residue depletion of Florfenicol (FF) and its metabolite Florfenicol Amine (FFA) after oral dose (25.0, 50.0 and 100.0 mg kg -1 body weight), once daily for 5 days. The residues were determined by High Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD). The maximum concentration of FF was all detected at 1 day in the albumen, yolk and whole eggs; the maximum concentration of FFA was detected at 1 day in the albumen and whole eggs, at 3 days in the yolk after cessation of medication. After oral administration of 100.0 mg kg -1, concentrations of FF and FFA were all below the LODs (1.5 μg kg -1 for FF and 0.5 ug kg -1 for FFA) at 7 days for the albumen, 11 days for yolk and 10 days for whole egg after cessation of medication. © Medwell Journals, 2012. Source


Xie K.,Yangzhou University | Xie K.,Key Laboratory for Animal Genetic | Jia L.,Yangzhou University | Jia L.,Key Laboratory for Animal Genetic | And 15 more authors.
Journal of Chromatographic Science | Year: 2012

A sensitive and robust method is presented for the simultaneous determination of amoxicillin (AMO) and ampicillin (AMP) in eggs by reversed-phase high-performance liquid chromatography with fluorescence detection (RP-HPLC-FLD). This method used a simple liquid-liquid extraction of the samples with acetonitrile and dichloromethane as precipitation of proteins and extraction solvent. AMO and AMP reacted with salicylaldehyde to form fluorescent derivatives, which were then analyzed with RP-HPLC-FLD. Separation was carried out on an Athena C18 column with a mobile phase consisting of 0.01M potassium dihydrogen phosphate, adjusted to pH 5.5 by 2M potassium hydroxide and acetonitrile. The detector response was linear over the tested concentration range from 5.0 to 800 ng/mL for AMO and AMP. The recovery values ranged from 78.4 to 88.7% for AMO and from 77.6 to 82.0% for AMP. The limits of detection were 1.2 for AMO and 0.4 μg/kg for AMP. The limits of quantification were 3.9 for AMO and 1.5 μg/kg for AMP. The corresponding intra-day and inter-day variation (relative standard deviation) were found to be less than 9.6 and 14.8%, respectively. © The Author [2012]. Published by Oxford University Press. All rights reserved. Source


Xie K.,Yangzhou University | Xie K.,Key Laboratory for Animal Genetic | Jia L.,Yangzhou University | Jia L.,Key Laboratory for Animal Genetic | And 16 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2011

A specific, sensitive and widely applicable reversed-phase high-performance liquid chromatography with fluorescence detection (RP-HPLC-FLD) method was developed for the simultaneous determination of thiamphenicol (TAP), florfenicol (FF) and florfenicol amine (FFA) in eggs. Samples were extracted with ethyl acetate-acetonitrile-ammonium hydroxide (49:49:2, v/v), defatted with hexane, followed by RP-HPLC-FLD determination. Liquid chromatography was performed on a 5μm LiChrospher C 18 column using a mobile phase composed of acetonitrile (A), 0.01M sodium dihydrogen phosphate containing 0.005M sodium dodecyl sulfate and 0.1% triethylamine, adjusted to pH 4.8 by 85% phosphoric acid (B) (A:B, 35:65 v/v), at a flow rate of 1.0mL/min. The fluorescence detector of HPLC was set at 224nm for excitation wavelength and 290nm for emission wavelength. Limits of detection (LODs) were 1.5μg/kg for TAP and FF, 0.5μg/kg for FFA in eggs; limits of quantitation (LOQs) were 5μg/kg for TAP and FF, 2μg/kg for FFA in eggs. Linear calibration curves were obtained over concentration ranges of 0.025-5.0μg/mL for TAP with determination coefficients of 0.9997, 0.01-10.0μg/mL for FF with determination coefficients of 0.9997 and 0.0025-2.50μg/mL for FFA with determination coefficients of 0.9998, respectively. The recovery values ranged from 86.4% to 93.8% for TAP, 87.4% to 92.3% for FF and from 89.0% to 95.2% for FFA. The corresponding intra-day and inter-day variation (relative standard deviation, R.S.D.) found to be less than 6.7% and 10.8%, respectively. © 2011 Elsevier B.V. Source


Zhao M.,Yangzhou University | Zhao M.,Key Laboratory for Animal Genetic | Xie K.-Z.,Yangzhou University | Xie K.-Z.,Key Laboratory for Animal Genetic | And 11 more authors.
Journal of Veterinary Pharmacology and Therapeutics | Year: 2015

A residue depletion study of ampicillin (AMP) was performed after oral dosing (60.0 mg/kg and 120.0 mg/kg body weight once a day for 5 days) to laying hens, through the use of reversed-phase high-performance liquid chromatography with fluorescence detection (RP-HPLC-FLD) to achieve detection of ampicillin residue in eggs. Limit of detection was 0.5 ng/g, and limit of quantitation was 1.2 ng/g for ampicillin. Extraction recoveries of ampicillin from samples fortified at 5.0-125.0 ng/g levels ranged from 77.5% to 84.6% in albumen, 77.9% to 87.5% in yolk, and 77.9% to 88.6% in whole egg, with coefficients of variation ≤9.3%. The maximum concentrations of ampicillin in albumen, yolk, and whole egg were detected at 1, 2, and 1 day after the last administration of ampicillin, respectively. Ampicillin was not detectable in albumen at day 9 of withdrawal time, at day 10 and 11 in yolk, and day 9 and 11 in whole egg at each of those 2 dose levels. The theoretical withdrawal time of AMP in whole egg was 6.730 and 7.296 days for 60 and 120 mg/kg oral dosage, respectively. This method also proved to be suitable as a rapid and reliable method for the determination of ampicillin in other poultry eggs. © 2015 John Wiley & Sons. Source


Sun L.,Yangzhou University | Sun L.,Key Laboratory for Animal Genetic | Jia L.,Nanjing Agricultural University | Xie X.,Nanjing Agricultural University | And 12 more authors.
Food Chemistry | Year: 2015

In this present study, we developed a simple, rapid and specific method for the quantitative analysis of the contents of amoxicillin (AMO), AMO metabolites and ampicillin (AMP) in eggs. This method uses a simple liquid-liquid extraction with acetonitrile followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The optimized method has been validated according to requirements defined by the European Union and Food and Drug Administration. Extraction recoveries of the target compounds from the egg at 5, 10 and 25 μg/kg were all higher than 80%, with relative standard deviations not exceeding 10.00%. The limits of quantification in eggs were below the maximum residue limits (MRLs). The decision limits (CCα) ranged between 11.1 and 11.5 μg/kg, while detection capabilities (CCβ) from 12.1 to 13.0 μg/kg. These values were very close to the corresponding MRLs. Finally, the new approach was successfully verified for the quantitative determination of these analytes in 40 commercial eggs from local supermarkets. © 2015 Elsevier Ltd. All rights reserved. Source

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