Synergistic highly sensitive electrochemical detection of enrofloxacin using Eichhornia crassipes-derived carbon dots and molecularly imprinted polymer networks

Excessive use of enrofloxacin has detrimental impacts on human health and the ecological environment. Consequently, there is an urgent need to develop a rapid, sensitive, and inexpensive platform for the detection of enrofloxacin. Herein, Eichhornia crassipes , an aquatic invasive plant, was utilized to prepare nitrogen-doped carbon dots for constructing the enrofloxacin-imprinted electrochemical sensor. The combination of nitrogen-doped carbon dots and multi-walled carbon nanotubes enhanced electrode conductivity and enriched active binding sites, improving sensor sensitivity. Meanwhile, highly biocompatible nicotinamide and L-cysteine were used as functional monomers to construct imprinting layers, enabling highly specific dual-site recognition of enrofloxacin. The sensor exhibited robust recognition capability for enrofloxacin under optimized conditions, offering a wide analytical range (0.05-100   μM) and low detection limit (0.0343   μM). Notably, the prepared sensor showed adequate recovery levels for analysis of real samples (fish flesh = 95.79%-110.59%, lake water = 97.22%-106.75%). Finally, the devised sensor performed favorably in the aqueous environment and meat products compared to standard methods, demonstrating its significant potential for trace enrofloxacin monitoring.