Electrochemical Immunosensor for Staphylococcal Enterotoxin B (SEB) Based on Platinum Nanoparticles‐Modified Electrode Using Hydrogen Evolution Inhibition Approach

In the present study, the electrocatalytic property of platinum for the reduction of protons to hydrogen in acidic medium is explored for the electrochemical detection of Staphylococcal Enterotoxin B (SEB). For this purpose glassy‐carbon electrodes (GCEs) were modified with platinum nanoparticles (Pt NPs) and studies were conducted on effect of copper deposition on the catalytic efficiency of Pt NPs towards reduction of protons. Linear sweep voltammetry (LSV) was performed to determine a negative shift of hydrogen evolution potential at the Pt NPs modified GCEs. In addition to this, indirect sandwiched ELISA procedure was followed on disposable SPEs. Anti‐mouse immunoglobulin G‐alkaline phosphatase (ALP) conjugate was immobilized on the SPE interface leads the hydrolysis of ascorbic acid 2‐phosphatase (AAP) and produce ascorbic acid which is responsible for the deposition of copper on Pt NPs modified GCEs. The potential for hydrogen evolution is negatively shifted with increasing the concentration of SEB over a range from 1.0 ng/mL to 1.0 µg/mL and the detection limit was found to be 1.0 ng/mL. The overall study emphasizes the role of catalytic efficiency of platinum nanoparticles and optimized conditions in providing better analytical performances for biosensors in term of sensitivity, selectivity and reliability.