Simple and rapid screening and confirmation of tetracyclines in honey and egg by a dipstick test and LC-MS/MS

The illegal use of antibiotics such as tetracyclines in honey production has recently been focused. The need for simple test methods has resulted in the development of a dipstick-test based on receptor binding, Tetrasensor®, Unisensor, Belgium. In this paper, two types of the test, the kit for analysis of tetracyclines in honey and the kit for analysis of tetracyclines in egg, fish and tissues from several animal species, have been evaluated and the results have been confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Different batches of Swedish honey and egg were analysed blank or spiked with oxytetracycline, tetracycline and chlortetracycline at 25 (honey) and 200 μg kg−1 (egg). The confirmation by LC-MS/MS was performed directly on diluted test extract without further purification (honey) or after a simple filtration (egg). This combination of a simple dipstick-test and LC-MS/MS proved to be a suitable and rapid way for the surveillance of tetracyclines in honey and egg.