Work

Thermal reduction synthesis approach of reduced graphene oxide for the preparation of a label-free and prompt immuno sensing of Salmonella enterica via electrochemical techniques

Year: 2025

Type: article

Abstract: This work comprises an immunosensor fabrication decorated with reduced graphene oxide (rGO) onto Indium tin oxide (ITO) coated electrodes to detect Salmonella enterica antigen. The rGO was synthesized with a modified Hummer technique and characterized via UV, XRD, FTIR, RAMAN and SEM techniques. The synthesized rGO was optimized at different concentrations to develop an immunosensor. An EDC-NHS interaction immobilized the monoclonal antibody against the selected antigen. Electrochemical techniques such as electrochemical impedance spectroscopy and cyclic voltammetry were deployed to characterize the modified electrodes in 5 mM Zobell's solution, followed by a differential pulse voltammetry analysis for sensor validation. The fabricated sensor has a 44 CFU/mL detection limit (LoD) and a 135 CFU/mL quantification limit (LoQ) with a linear range of 10 1 –10 7 CFU/mL. This proposed immunosensor can be applied to any sample containing traces of Salmonella enterica. • Development of a Highly Sensitive Immunosensor: A low detection limit of 44 CFU/mL, significantly surpassing traditional culture-based methods . • Optimization of Electrode Fabrication : The optimal concentration of rGO (1 mg/mL) and anti-Salmonella antibody dilution (1:100) were identified, along with an incubation time of 30 min for effective antigen-antibody interaction, ensuring maximum sensor performance . • Excellent Specificity and Selectivity : The fabricated immunosensor exhibited high specificity towards Salmonella enterica with negligible interference against E . coli and B . brevis . • Rapid and Efficient Detection : Qualitative detection of Salmonella enterica within 40 mins, significantly reducing the time required compared to conventional techniques, which take several days . • Validation through Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) : The stepwise immunosensor fabrication were successfully verified using CV and EIS, confirming the efficacy of the biosensor.

Source: Sensing and Bio-Sensing Research

DOI: 10.1016/j.sbsr.2025.100789

Authors: Nahid Rehman, Ashutosh Pandey, Ashutosh Pandey, Anjana Pandey, Anjana Pandey

Institution: Motilal Nehru National Institute of Technology

Language: English

Topic: Electrochemical sensors and biosensors

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,850