The work was focused on monitoring the stability of the tetracycline antibiotics oxytetracycline, tetracycline and chlortetracycline during sample processing and on optimising the analytical procedure for the determination of tetracycline antibiotics in honey. Stability was tested on standard solutions of tetracyclines in the most commonly used solvents – water, methanol and Na2EDTA-McIlvaine buffer (citrate phosphate buffer). Subsequently, the preparation procedure was optimised on model honey samples spiked with tetracycline antibiotics at the concentration levels 1, 2 and 4 mg·l-1 using Na2EDTA-McIlvaine buffer as a solvent. The stability of the tetracycline antibiotics was monitored for thirty days at an interval of 3 times a week. Antibiotics were determined by reversed-phased high-performance liquid chromatography with UV detection. Degradation of a multi component standard of tetracycline antibiotics was 69 – 85% in water, 28 – 61% in methanol and 46 – 53% in the Na2EDTA-McIlvaine buffer. Degradation of a mixed standard of tetracyclines in samples of honey at the selected concentrations was 2 – 61%.
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