High-Efficiency Electrochemical Sensor for Chloramphenicol Detection: Innovative Modification with CoFe2O4@Rod-Shaped Fe-BTC and CoFe2O4@Spherical Fe-BTC Nanocomposites

Abstract CoFe2O4(CFO)@Fe-BTC nanocomposite structures were comprehensively investigated, focusing on their morphological characteristics, size distribution, and electrochemical properties. Notably, the Fe-BTC framework substrates with spherical nanoparticle and rod-shaped morphologies were synthesized via hydrothermal and electrochemical methods, respectively. The structural and electrochemical behaviors of the synthesized materials were characterized using various analytical techniques, including X-ray diffraction, scanning electron microscopy, cyclic voltammetry, chronoamperometry, and differential pulse voltammetry. Electrochemical measurements conducted in 0.1 M phosphate-buffered saline solution facilitated the evaluation of chloramphenicol detection performance at the modified electrodes. In which, many unique features of these nanocomposites were attributed to the synergistic integration of the highly porous Fe-BTC frameworks, their stability, large surface area, and the incorporation of CFO NPs with a high density of active sites, strong catalytic activity, and good electrical conductivity. These combined characteristics contributed to the formation of nanocomposites with superior electrochemical performance, particularly for the CFO@rod-shaped Fe-BTC nanocomposite, which revealed a broad linear concentration range of 0.5–50 µM and a notably low limit of detection of 0.18 µM. Thus, CFO@Fe-BTC 2 sample emerges as a promising candidate for electrochemical sensor applications, demonstrating high detection capability and environmental compatibility for monitoring antibiotic residues in food samples.