​Screening for Enrofloxacin and Ciprofloxacin Residues in Chicken Liver by Liquid Chromatography Tandem Mass Spectrometry Accompanied by Optimal Liquid-liquid Extraction with Phosphoric Acid

Abstract

Background: Enrofloxacin used considerably on large scale among poultry birds. Detection and monitoring of its residues is vital in the domestic and export market. A simple and rapid LCMS/MS method for screening of Enrofloxacin and its metabolite residues in poultry liver samples was described. Methods: Target analytes were extracted with a solvent combination of 5% phosphoric acid in 50% acetonitrile in water. It was followed by deep freezing for efficient separation of the liquid phase. Later extractants were subjected to centrifugation at 4oC, 10,000 rpm for 20 minutes and supernatant was filtered and injected into LCMS/MS. 0.1% formic acid is used as mobile phase additive for both aqueous and organic mobile phase acetonitrile. Result: Accuracy and precision values of the method are within the acceptable limit of ( less than 5% RSD) accorded by the European commission. Standardized method has been applied to determine the Enrofloxacin and Ciprofloxacin residues in liver samples collected in local markets and found within maximum residue limits.