Fabrication and application of functionalized carbon nanotubes for highly sensitive and selective sensing of enrofloxacin

This paper introduces an innovative electrochemical sensor that detects enrofloxacin (ENR) utilizing a glassy carbon electrode (GCE) modified with reduced carbon nanotubes (rCNT). The fabrication process involved a simple drop‐coating technique using water‐soluble oxidized CNTs (oCNT), followed by electrochemical reduction to obtain the rCNT/GCE electrode. The electrochemical properties of the modified electrodes, including GCE, CNT/GCE, oCNT/GCE, and rCNT/GCE, were evaluated using cyclic voltammetry and electrochemical impedance spectroscopy. The results demonstrated significantly improved electrochemical surface area and faster electron transfer rate for the rCNT/GCE electrode compared to the other configurations. Consequently, the rCNT/GCE electrode exhibited the highest electrochemical signal for ENR detection. Under optimized conditions, the rCNT/GCE‐based sensor displayed excellent performance for ENR detection. It achieved a low detection limit of 0.002 µ m and demonstrated linearity within the ranges of 0.005–0.05 µ m and 0.05–1.5 µ m . Furthermore, the proposed sensor exhibited good selectivity, as well as excellent repeatability and reproducibility. To assess the sensor's practical utility, a quantitative analysis of ENR in shrimp meat samples was conducted. The results demonstrated the high sensitivity and accuracy of the proposed sensor in quantifying ENR, highlighting its potential as a reliable tool for environmental monitoring of water resources.