A HPLC with fluorescence detection method for the determination of tetracyclines residues and evaluation of their stability in honey

A high-performance liquid chromatography with fluorescence detection method for the simultaneous determination of oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) residues in honey was developed and validated. Sample preparation was done in a single solid phase extraction step. The chromatographic separation was performed on a C8 column. Matrix matched calibration curves showed linearity higher than 0.99. The accuracy values lay between 86% and 111% and the precision was lower than 11%. Limits of detection and quantitation were 8 μg kg−1 and 25 μg kg−1, respectively. The method was employed to evaluate the stability of the tetracyclines in honey during 60 days of storage. The residue levels of OTC, TC and CTC were reduced 97%, 76% and 71%, respectively. Honey samples (n = 22) collected from the retail market were analyzed. No tetracyclines residues were detected.