Ultrasensitive Detection of Chlortetracycline in Animal-Origin Food Using Molecularly Imprinted Electrochemical Sensor Based on Synergistic Interaction of Nanoflower Sns2/Znco-Mof and Aunps

Abstract

The chlortetracycline (CTC) residue in food poses a threat to human health. Therefore, developing sensitive, convenient, and selective analytical methods for CTC detection is crucial. This study innovatively uses tin disulfide/bimetallic organic framework nanocomposites (SnS2/ZnCo-MOF) in conjunction with gold nanoparticles (AuNPs) to co-modify a glassy carbon electrode (GCE). Further, a molecularly imprinted electrochemical sensing platform Au-MIP/SnS2/ZnCo-MOF/Au/GCE (AZG) was fabricated for selective CTC detection. SnS2/ZnCo-MOF enhanced the stability and surface area of AZG sensor. The presence of AuNPs facilitated electron transport between the probe and the electrode across the insulating molecularly imprinted polymer (MIP) layer. The fixation of AuNPs and MIP via electropolymerization enhanced the selective recognition of this sensor and amplified the output signal. The AZG sensor demonstrated a wide linear detection range (0.1–100 μM), low detection limit (0.072 nM), and high sensitivity (0.830 μA μM−1). It has been used for detecting CTC in animal-origin food with good recovery (96.08%–104.60%).

Keywords: Molecular imprinting, Electrochemical sensor, Chlortetracycline, Bimetallic organic frameworks, Au nanoparticles, Animal-origin food