Electrochemical Aptasensor for Selective and Sensitive Detection of Staphylococcus aureus Using Graphene oxide/poly Deep Eutectic Solvent/Nickel Oxide Nanocomposite Modified Electrode

Since that pathogenic bacteria are major threats to human health; this research describes the fabrication of an effective and sensitive platform based on graphene oxide/poly deep eutectic solvent/nickel oxide nano particles (GO/PDES/NiO NPs) nanocomposite at the surface of glassy carbon electrode for selective detection of Staphylococcus aureus (S. aureus). The DNA aptamers were immobilized on the modified electrode through the EDC/NHS chemistry. Each aptasensor modification step was checked by with cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) techniques. The linear dynamic range of the proposed electrochemical aptasensor covered a large variation of S. aureus concentrations from 10(1) - 10(8) CFU.mL(-1) and a detection limit of 10 CFU.mL(-1) under optimum conditions was obtained. Analysis of spiked tap water, lake water and human serum samples revealed high potential of this aptasensor as a sensitive, effective, and label-free promising tool for S. aureus detection. This is the first time that poly deep eutectic solvents used in live bacteria detection.