Cus@rGO Grafted PEDOT:PSS Paper-Based Electrochemical Biosensor for Sensitive Detection of Fenitrothion

Abstract

This paper introduced an innovative paper-based biosensor outlined for the precise and rapid detection of fenitrothion pesticide. In this work, CuS@rGO grafted PEDOT:PSS-based conducting paper has been fabricated by simple dip coating method. Further, the CuS@rGO/PEDOT:PSS/WP electrodes were doped with multiple organic solvents such as methanol, ethylene glycol (EG), dimethyl sulfoxide (DMSO), N,N-dimethyl formamide (DMF), and N-methyl pyrrolidone (NMP) to enhance the electrochemical parameters. Among all these solvents, the electrode doped with DMSO is found to have the highest conductivity. Subsequently, AChE enzyme is immobilized onto the modified electrode to accelerate the particular recognition of fenitrothion using glutaraldehyde as a cross-linking agent. Electrochemical studies have shown that this conducting paper-based electrode possesses high sensitivity and low detection limit of 0.505 mA/pM and 0.28 pM, respectively, under a physiological range of 1–80 pM for fenitrothion (FNT) detection. This paper electrode may be a very promising alternative to ITO, gold and glassy carbon electrodes, which are known to have few uses because of their high cost, fragility, restricted flexibility, and environment concerns. The recommended biosensor's accuracy was well evaluated in two real samples like rice and tomato thereby increasing its suitability for FNT detection in real-world circumstances.