DEVELOPMENT OF LATERAL FLOW IMMUNOASSAY FOR RAPID DETECTION OF OXYTETRACYCLINE IN HONEY SAMPLES

Abstract

A lateral flow immunoassay (LFIA) was developed in the competitive reaction format and applied to test residues of the antimicrobial oxyteracycline (OTC) in honey samples. To prepare the assay test, a nitrocellulose membrane was stripped with hapten OTC3 conjugate to ovoalbumin egg protein (OVA-OTC3) and goat anti-rabbit antisera (GAR) as capture and control reagents, respectively. Polyclonal antisera against oxyteracycline was conjugated to colloidal gold nanoparticles and used as the detection reagent. The visual detection limit (cut-off value) of the oxyteracycline LFIA was 20 ng/g, and qualitative results were obtained within 10 min without expensive equipment. The assay was evaluated with OTC spiked honey samples from different geographical origin (n = 25). The results were in good agreement with those obtained from liquid chromatography separation and mass spectroscopy detection (LC-MS), indicating that the LFIA test might be used as a semiquantitative method for the determination of oxyteracycline. The system was also highly specific, showing no cross-reactivity to other chemically similar antibiotics.