Development and Validation of an HPLC Method for the Determination of Seven Tetracycline Antibiotics Residues in Chicken Muscle and Egg Yolk According to 2002/657/EC

Abstract

Herein, an HPLC method with diode-array detection, at 355 nm, is described for the determination of seven tetracyclines in chicken muscle and egg yolk: minocycline, tetracycline, oxytetracycline, methacycline, demeclocycline, chlortetracycline, and doxycycline. The examined TCs were extracted from chicken muscle with 15% TFA and 0.4 M oxalate buffer (pH 4) and from egg yolk with 40% TFA and 0.4 M oxalate buffer (pH 4). LiChrolut and Nexus SPE cartridges were used for further purification of chicken tissue and egg yolk extracts, respectively, with 0.01 M C2H2O4/CH3CN/CH3OH (40:30:30 v/v/v) as elution solvent. The separation was achieved on a Kromasil ODS-3, 5 µm, 250 × 4 mm, analytical column. The mobile phase, a mixture of 0.01 M oxalic acid and CH3CN, was delivered using a gradient program. The procedure was validated according to the Decision 2002/657/EC, determining selectivity, stability, decision limit, detection capability, accuracy, and precision. Overall recoveries ranged from 92–110.1% and 89–106% for chicken tissues and eggs, respectively. All RSD values were lower than 11%. The decision limits CC a in chicken tissues ranged from 102.98 to 109.11 µg/kg, while detection capability CC b from 113.45 to 118.18 µg/kg. Respective values in eggs were 206.53–214.60 µ g/kg for CC a and 216.21–228.97 µg/kg for CC b .