A Highly Sensitive Cu-Co MOF/MoSe₂‑Based Electrochemical Sensor for Real-Time Monitoring of Ofloxacin in...

The development of fast, precise, and cost-effective monitoring devices is necessary to address the growing number of alarms arising from the persistence of antibiotics in aquatic environments. Molybdenum diselenide (MoSe₂) nanosheets and Cu-Co metal organic framework (MOF) were used in the present investigation to design a synergistic electrochemical sensing platform for ofloxacin determination. The Cu-Co MOF is combined with MoSe₂ to make a composite, namely, Cu-Co MOF/MoSe₂. The X-ray diffraction (XRD) analysis shows the planes and crystalline size of the prepared materials. The SEM analysis reveals the flower-like structure morphology of the composite material (MOF/MoSe₂). The electrochemical characterization of the synthesized material has been investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Compared to the single components, the redox reactions of the composite were significantly enhanced by CV and DPV. DPV was performed to determine the limit of detection (LOD) and sensitivity of the prepared materials. The resulting sensitivity of Cu-CO MOF/MoSe₂ is 74.251 μA/μM.cm² and the limit of detection is 1.74 pM (picomolar). The limit of quantification (LOQ) is 5.7973 pM, with a linear range of 0.5-10 μM. Besides its low detection limit and wide linear range, the sensor also demonstrated superior repeatability, reproducibility, and selectivity toward common interferents, including metal ions, glucose, and other antibiotics. Its environmental monitoring application for antibiotic pollutants was demonstrated by its favorable recovery in spiked water samples. The Cu-Co MOF/MoSe₂ hybrid material can be a potential electrochemical sensing material for the rapid and precise detection of ofloxacin in real samples.