Mefenamic acid (MFA) is a non-steroidal anti-inflammatory drug widely used for its analgesic and anti-inflammatory properties. Overuse of this drug can lead to the accumulation of toxic metabolites, potentially leading to heart attacks, acute liver necrosis, and increased mortality [۱]. Consequently, MFA is classified as a priority pollutant in the European Union, emphasizing the critical need for its sensitive detection in biological and environmental samples [۲].
Metal-organic frameworks (MOFs) have attracted considerable attention from researchers in the fields of catalysis and sensing due to their large surface area and tunable chemical properties, including porous materials. The presence of metal nodes connected by organic linkers provides a versatile platform for various applications. Among various transition metals, copper-based MOFs (Cu-MOFs) have received considerable attention as potential electrocatalysts. This work faces this challenge by the development of a novel electrochemical sensor via modifying a pencil graphite electrode (PGE) with sustainable Cu-MOFs and their corresponding novel composites combined with GO and Cu/Al LDH to create a new Cu-MOF/Cu/Al LDH/GO-PGE sensor for the detection and measurement of MFA drug. The morphological characterization was carried out by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). By using cyclic voltammetry (CV), chronoamperometry, and differential pulse voltammetry (DPV) techniques in phosphate buffer solution (PBS) at pH ۷.۰ as a supporting electrolyte, an analytical method for the measurement of MFA was established. CV results show that the Cu-MOF/Cu/Al LDH/GO nanocomposite modified PGE has a considerable rise in anodic and cathodic peak current compared to the unmodified PGE and exhibits good activity for the electrochemical reaction of MFA. The constructed sensor displayed a good response with a detection limit (۳Sb/m) of ۰.۰۰۵ μM and wide dynamic concentration range from ۰.۰۱ to ۱۰۰.۰ μM for MFA. Furthermore, the Cu-MOF/Cu/Al LDH/GO-PGE showed great selectivity and anti-interference capabilities. Additionally, the sensor demonstrated excellent reproducibility and stability, making it an ideal tool for the determination of MFA in real samples.