Polythiophene functionalized Ti3C2Tx-TiO2 nanorods composite based electrochemical sensing platform for the detection of Pseudomonas aeruginosa DMC-27b

Due to its ability to form antibiotic-resistant biofilms, Pseudomonas aeruginosa can cause serious, long-lasting infections, especially in individuals with weakened immune systems; therefore, its rapid detection is crucial for effective treatment. Herein, a polythiophene-functionalized Ti₃C₂T_x-TiO₂ nanorods (NRs) based electrochemical capacitive biosensor is proposed for the determination of Pseudomonas aeruginosa DMC-27b. The capacitive characteristics of the modified electrode were evaluated using a combination of electrochemical methods, such as electrochemical impedance spectroscopy, cyclic voltammetry, galvanostatic discharge, and self-discharging. The incorporation of Ti₃C₂T_x-TiO₂ NRs significantly enhanced both conductivity and charge storage, yielding a specific capacitance of 973.07 F/g. The biosensor demonstrated a sensitive detection range of 10–10⁶ CFU/ml, with a limit of detection of 1.0 CFU/ml. This is the first report on the synthesis of Ti₃C₂T_x-TiO₂ NRs and Ti₃C₂T_x-TiO₂ NRs-doped PTh nanocomposites, and the development of Ti₃C₂T_x-TiO₂ NRs@PTh based electrochemical capacitive biosensor for the detection of Pseudomonas aeruginosa. The biosensor, even with a gradual decline in phage activity, showed good recovery with promising results for detecting the superbug in real samples. Furthermore, the developed Ti₃C₂T_x-TiO₂ NRs@PTh/Phage biosensor exhibited highly selective detection of Pseudomonas aeruginosa DMC-27b, as confirmed by host range and spot test results, and further demonstrated excellent reproducibility and stability.