Construction of a Biosensor Based on a Combination of Cytochrome c, Graphene, and Gold Nanoparticles

Abstract

A biosensor based on a combination of cytochrome c (Cyt c), electrochemical reduced graphene oxides (ERGO), and gold nanoparticles (AuNPs) on a glassy carbon electrode (GCE) was fabricated. The proposed biosensor electrode was denoted as GCE/ERGO-Nafion/AuNPs/Cyt c/Nafion, where ERGO-Nafion was deposited by dropping graphene oxides-Nafion mixed droplet first and following electrochemical reduction, AuNPs were directly deposited on the surface of the ERGO-Nafion modified electrode by electrochemical reduction, and other components were deposited by the dropping-dry method. The effect of the deposition amount of AuNPs on direct electrochemistry of Cyt c in the proposed electrode was investigated. The hydrogen peroxide was taken to evaluate the performance of the proposed biosensor. The results showed that the biosensor has great analytical performance, including a high sensitivity, a wide linear range, a low detection limit, and good stability, reproducibility, and reliability.

Electrocatalysis by Heme Enzymes—Applications in Biosensing

“…Detection of H 2 O 2 has been achieved with cyt c adsorbed or entrapped on different nanostructured electrodes, including (i) Au/Fe 2 O 3 /N-doped CNT composites [241]), (ii) three-dimensional graphene aerogels in the presence of AuNPs [242], (iii) mixtures of MWCNTs and conductive polymers, namely PANI [239] or PPY [243], and (iv) AuNPs grown on electrochemically reduced graphene oxide/Nafion composites [244]. In a recent work, cyt c was adsorbed on a l-cysteine layer deposited onto a hybrid conducting polymer/MWCNT modified GC electrode [128].…”

Optimization of the Electrodeposition of Gold Nanoparticles for the Application of Highly Sensitive, Label-Free Biosensor

“…The detectable electron dense core of AuNPs with the high surface to volume ratio, and the controllable electrochemical behavior have all made AuNPs been widely used as sensitive tracers for biomolecular recognition events. [23,24,25]. Thus, in this work, the AuNPs were selected to form a thin film on the substrate of electrode with electrodeposited method, to act as an amplification platform for high sensitivity detection of biomolecules with potentiometric methods.…”

“…In electrodeposition, the size of nanoparticle has substantial effects on protein structure and stability compared to relatively “flat” supports [25,26]. For the flat substrates with nanoscale roughness, the effect of AuNPs size on protein interaction has not been widely studied.…”

Optimization and Analytical Behavior of Electrochemical Sensors Based on the Modification of Indium Tin Oxide (ITO) Using PANI/MWCNTs/AuNPs for Mercury Detection

“…Composites made from a conductive polymer, such as polyaniline (PANI), and nanoparticles, such as multiwalled carbon nanotubes (MWCNTs) and gold nanoparticles (AuNPs), have been widely used in electrochemical sensors. The synergistic action between the high conductivity and stability of PANI [ 10 ], the high aspect ratio and exceptional mechanical strength of MWCNTs [ 11 ] and favorable electrocatalytic behavior of AuNPs could greatly enhance the sensor sensitivity and electroanalytical signals [ 12 , 13 ]. In this perspective, herein, for the first time, a PANI/MWCNT/AuNP-modified ITO electrode was developed by the direct electrodeposition of PANI, MWCNTs and AuNPs on a film-coated ITO electrode.…”