Sensitive detection of pefloxacin using UiO-67 MOF functionalized with carboxylated multi-walled carbon nanotube

Developing a simple and efficient detection method for pefloxacin (PEF) is crucial for environmental monitoring and food safety assurance. In this study, we designed a novel electrochemical sensor for PEF detection by integrating zirconium-based metal-organic frameworks (UiO-67 MOFs) with carboxylated multi-walled carbon nanotubes (MWCNT-COOH) through a two-step hydrothermal and ultrasonic-assisted strategy. The coordination of the carboxyl groups of MWCNT-COOH with the unsaturated metal sites on the zirconium clusters of UiO-67, and the strong electrostatic attraction between PEF and the negatively charged composite surface, as well as strong π-π stacking interactions between the aromatic ring of PEF and the benzene rings of the organic ligands in UiO-67 and the graphite surface of MWCNT-COOH, collectively contribute to the efficient accumulation and sensitive detection of PEF. The sensor demonstrated a wide linear range (0.01–10 μM), an ultralow detection limit (0.005 μM), and outstanding overall sensing performance. When applied to real-world samples, including lake water and honey, the method achieved satisfactory recovery (94.48% − 108.9% and 100.9% to 106.4%, respectively), confirming its practical applicability for monitoring PEF in environmental and food matrices.