Fluorescence resonance energy transfer-based aptasensor for sensitive detection of kanamycin in food

Kanamycin (KAN) is widely used in animal husbandry to treat bacterial infections. However, excessive KAN may cause residues and be transmitted to humans and the environment, causing serious adverse effects on humans. Herein, a simple fluorescence resonance energy transfer (FRET)-based aptasensor has been developed for sensitive detection of KAN in food. In the absence of KAN, UCNPs-aptamer hybridized with BHQ3-cDNA and quenched fluorescence was observed due to the FRET effect between BHQ3 and UCNPs. In the presence of KAN, double strands separated and the fluorescence intensity was recovered. Additionally, a linear relation (R2 = 0.9926) was found in the range of 0.05–50 μM and the recovered fluorescence intensity at 654 nm with a detection limit of 18.9 nM. The method was verified by standard recovery method and HPLC with satisfactory recovery rate (87.0–109.6%) and accuracy (P > 0.05). These results showed the proposed method could be successfully applied to detect KAN in food samples.