Real-Time and Selective Detection of Pseudomonas aeruginosa in Beef Samples Using a g-C3N4-Doped Multimetallic Perovskite-Based Electrochemical Aptasensor

The alarming rise in foodborne illnesses, particularly those associated with microbial contamination in meat products, presents a serious challenge to global food safety. Among these microbial threats, <i>Pseudomonas aeruginosa</i> (<i>P. aeruginosa</i>) poses a critical threat due to its biofilm-forming capability and prevalence in contaminated beef, highlighting its effective real-time detection. Herein, we report the fabrication of a novel electrochemical aptasensor based on multimetal perovskite (FeCoCuNiO) doped with urea-derived graphitic carbon nitride (g-C₃N₄), synthesized via a sol-gel combustion method. The FeCoCuNiO-g-C₃N₄ nanocomposite was then coated onto a graphitic pencil electrode and functionalized with a DNA-based aptamer specific towards <i>P. aeruginosa</i>. The resulting aptasensor exhibited a low detection limit of 3.03 CFU mL^-1 with high selectivity and sensitivity, and was successfully applied to real-time detection of <i>P. aeruginosa</i> in food samples. To the best of our knowledge, this work presents the first FeCoCuNiO-g-C₃N₄-based aptasensor for bacterial detection, offering a promising platform for food safety assurance and public health protection.