Electrochemical determination of levofloxacin with a Cu–metal–organic framework derivative electrode

Levofloxacin (LEV) is used in pharmaceuticals to treat bacterial infections, but is rarely metabolized by the human body, and hence, largely excreted. This leads to its accumulation in sewage, posing hazards to human health and the environment. Considering the drawbacks of existing methods to detect LEV, including a high cost, significant analysis time, and complex sample processing, the aim of this study was to devise an optimal detection method for LEV. A modified screen-printed electrode (SPE) using a Cu–metal–organic framework (MOF) derivative was proposed as an electrochemical sensor for LEV detection. They were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The prepared Cu-MOF derivative offered a large specific surface area and highly dispersed active sites, which facilitated full contact with LEV. The electrochemical behavior of LEV was evaluated using cyclic voltammetry (CV) in the potential range of − 0.2 to 1 V. The linear response range was 0.1–100 μM, sensitivity was 1855 μA^.mM^−1.cm⁻², and detection limit was 0.016 μM. The detection limit and sensitivity of differential pulse voltammetry (DPV) were 0.17 μM and 183 μA^.mM^−1.cm⁻², respectively. The detection limit and sensitivity of chronoamperometry (CA) were 0.037 μM and 825 μA^.mM^−1.cm⁻², respectively. The method exhibited significant selectivity and stability. The use of this electrochemical sensor containing the Cu-MOF derivative constitutes a simple and rapid method for determining LEV in medicine and the food industry.