Synthesis of rod-like metal–organic framework materials as an electrochemical aptamer sensor for sensitive detection of tetracycline

Abstract

Due to the wide application of tetracycline (TC), there will be residues in human food consumed daily. It is important to develop sensitive and rapid detection methods for TC in food. In this study, a rod-like NH₂-MIL-68(In) material was developed as a DNA probe binding site for rapid detection of TC. The aptamer and NH₂-MIL-68(In) were tightly bound by glutaraldehyde. After the addition of TC, the aptamer specifically adsorbs TC in the test sample, resulting in increased impedance on the electrode and decreased electrical signal. Under optimized conditions, the sensor had a wide detection range (0.001–100 μM) and a low detection limit (0.36 nM). In addition, the NH₂-MIL-68(In)@Apta sensor was successfully applied to TC residues in milk samples with recoveries of 84.33–117.22%. The results showed that our work can provide a new strategy for the direct detection of TC in food samples.