Electrochemical Detection of β‐Lactoglobulin Allergen Using Titanium Dioxide/Carbon Nanochips/Gold Nanocomposite‐based Biosensor

Abstract

Abstract A label‐free electrochemical immunosensor was developed for the ultra‐sensitive detection of β‐lactoglobulin (β‐LG). The novel nanocomplex of carbon nanochips, colloidal gold nanoparticles and titanium dioxide nanoparticles TiO 2 /CNC/AuC were constructed on conducting polymer, chitosan, and were characterised using scanning electron microscopy (SEM) and energy‐dispersive X‐ray spectroscopy (EDX). This nanocomplex interface was studied using cyclic voltammetry (CV) and showed great improvement at the gold electrode surface with enhanced electrochemical performance, sensitivity and selectivity for β‐lactoglobulin. Under optimal parameters, the square wave voltammetry (SWV) response curve was determined from 0.01 pg/mL to 500 pg/mL using [Fe(CN) 6 ] 3−/4− ] redox probe. The calibration plot illustrates a linear relationship between log β‐LG concentration and SWV current, with the limit of detection determined to be 0.01 pg/mL. This immunosensor displayed high sensitivity, selectivity, reproducibility and stability, and can be utilised for the detection of β‐LG in real food samples.