Development and Validation of an HPLC Confirmatory Method for the Determination of Seven Tetracycline Antibiotics Residues in Bovine and Porcine Muscle Tissues According to 2002/657/EC

Abstract

An HPLC method with diode array detection, at 355 nm, was developed and validated for the determination of seven tetracyclines (TCs) in bovine and porcine muscle tissues. Examined tetracyclines include: minocycline (MNC), tetracycline (TC), oxytetracycline (OTC), methacycline (MTC), demeclocycline (DMC), chlortetracycline (CTC), and doxycycline (DC). These were extracted from tissues using oxalate buffer (pH 4). Samples were purified by SPE on Nexus cartridges, using MeOH/ACN/0.05 M C2H2O4 (30:30:40 v/v/v) as elution solvent. The separation was achieved on a Kromasil C18, 5 µm, 250 × 4 mm, analytical column, operating at ambient temperature. The mobile phase, a mixture of A: 0.01 M oxalic acid and B: CH3CN, was delivered using a gradient program. The procedure was validated according to the Decision 2002/657/EC, by determining selectivity, stability, decision limit, detection capability, accuracy, and precision. Overall recoveries of TCs from bovine and porcine samples ranged from 89–114.1%. All RSD values were lower than 8.5%. The decision limits CCa in bovine tissues ranged from 103.2 to 111.1 µg/kg, while detection capability CCb from 105.2 to 114.9 µg/kg. Respective values in porcine tissues were 102.5–106.4 µg/kg for CCa and 105.3–108.7 µg/kg for CCb.