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

Abstract

A highly sensitive electrochemical biosensor with a signal amplification platform of electrodeposited gold nanoparticle (AuNP) has been developed and characterized. The sizes of the synthesized AuNP were found to be critical for the performance of biosensor in which the sizes were dependent on HAuCl4 and acid concentrations; as well as on scan cycles and scan rates in the gold electro-reduction step. Systematic investigations of the adsorption of proteins with different sizes from aqueous electrolyte solution onto the electrodeposited AuNP surface were performed with a potentiometric method and calibrated by design of experiment (DOE). The resulting amperometric glucose biosensors was demonstrated to have a low detection limit (> 50 μM) and a wide linear range after optimization with AuNP electrodeposition.

A switchable electrochemical hairpin-aptasensor for ochratoxin A detection based on the double signal amplification effect of gold nanospheres

“…However, according to previous studies, too thick a GNSs film would not improve the performance of the interface. 31 As shown in Fig. 3, with the extension of the deposition time, the peak current of CV also increased and reached the maximum at 40 s. It is reasonable to think that a thicker GNSs deposition will impede electron transfer.…”

Detection of a Double-Stranded MGMT Gene Using Electrochemically Reduced Graphene Oxide (ErGO) Electrodes Decorated with AuNPs and Peptide Nucleic Acids (PNA)

“…This peak has shifted to 0.5 V in the next cycles, indicating the easier electro-deposition of gold and the growth of the AuNPs. The Anodic peak at 0.8 V can be ascribed to the surface oxidation of the AuNPs [ 40 , 41 , 42 ].…”

Role of Defects of Carbon Nanomaterials in the Detection of Ovarian Cancer Cells in Label-Free Electrochemical Immunosensors

“…The deposition of AuNPs@carbon/GCE is shown in Figure S1 . At first cycle, a reduction peak is observed at ~0.27 V, and the next cycle involves a shift to a more positive potential, enabling easier gold electrodeposition on the existing gold particles [ 38 ]. The reduction of Au is shown in Equation (1) [ 39 ].…”