Development of a biosensor platform based on ITO sheets modified with 3-glycidoxypropyltrimethoxysilane for early detection of TRAP1

Abstract

The aim of this research was to design an electrochemical immunosensor for determination of tumournecrosis factor receptor-associated protein-1(TRAP1) antigen, a heat shock protein linked to tumour necrosis factor.The indium-tin oxide covered polyethylene terephthalate (ITO-PET) electrode surface was cleaned and was prepared forthe introduction of hydroxyl groups on its surface by using NH4 OH/H2 O2 /H2 O. As a silanization agent for covalentattachment of anti-TRAP1 on the surface of the ITO working electrode, 3-glycidoxypropyltrimethoxysilane (3-GOPS)was used. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterizethe immobilization steps. A variety of parameters, 3-GOPS and anti-TRAP1 concentrations, and anti-TRAP1 andTRAP1 incubation durations were optimized. After determining the optimum conditions, characterization studies suchas repeatability, reproducibility, regeneration, square wave voltammetry, and single frequency impedance were performed.The electrochemical immunosensor has presented an extremely wide determination range for TRAP1 from 0.1 pg/mL to 100 pg/mL.