Electrochemical Impedance Characterization of Cell Growth on Reduced Graphene Oxide–Gold Nanoparticles Electrodeposited on Indium Tin Oxide Electrodes

Abstract

The improved binding ability of graphene–nanoparticle composites to proteins or molecules can be utilized to develop new cell-based assays. In this study, we fabricated reduced graphene oxide–gold nanoparticles (rGO-AuNP) electrodeposited onto a transparent indium tin oxide (ITO) electrode and investigated the feasibility of the electrochemical impedance monitoring of cell growth. The electrodeposition of rGO–AuNP on the ITO was optically and electrochemically characterized in comparison to bare, rGO-, and AuNP-deposited electrodes. The cell growth on the rGO–AuNP/ITO electrode was analyzed via electrochemical impedance measurement together with the microscopic observation of HEK293 cells transfected with a green fluorescent protein expression vector. The results showed that rGO–AuNP was biocompatible and induced an increase in cell adherence to the electrode when compared to the bare, AuNP-, or rGO-deposited ITO electrode. At 54 h cultivation, the average and standard deviation of the saturated normalized impedance magnitude of the rGO–AuNP/ITO electrode was 3.44 ± 0.16, while the value of the bare, AuNP-, and rGO-deposited ITO electrode was 2.48 ± 0.15, 2.61 ± 0.18, and 3.01 ± 0.25, respectively. The higher saturated value of the cell impedance indicates that the impedimetric cell-based assay has a broader measurement range. Thus, the rGO–AuNP/ITO electrode can be utilized for label-free and real-time impedimetric cell-based assays with wider dynamic range.

Special Issue on Nano-Biointerface for Biosensing

“…S.R. Chinnadayyala and coworkers in their article: Electrochemical Impedance Characterization of Cell Growth on Reduced Graphene Oxide-Gold Nanoparticles Electrodeposited on Indium Tin Oxide Electrodes [7], describe the fabrication of reduced graphene oxide-gold nanoparticles (rGO-AuNP) electrodeposited onto a transparent indium tin oxide (ITO) electrode and investigate the feasibility of monitoring HEK293 cell growth by electrochemical impedance, in combination with the microscopic observation of the cells transfected with a green fluorescent protein expression vector. Results demonstrate the high potentiality of the rGO-AuNP/ITO electrode for label-free and real-time impedimetric cell-based assays, since the rGO-AuNP hybrids are biocompatible and induce an increase in cell adherence to the electrode when compared to the bare, AuNP-, or rGO-deposited ITO electrode.…”

Osteogenic Potential of a Polyethylene Glycol Hydrogel Functionalized with Poly-Lysine Dendrigrafts (DGL) for Bone Regeneration

“…PLL functions as an attachment factor that enhances cell adhesion due to its strong affinity to proteins and electrostatic interactions between the positive charges on the PLL molecule and the negative charges on the cell membrane [ 17 ]. Thus, PLL is commonly used to enhance cell adhesion, spreading, proliferation and differentiation [ 18 , 19 , 20 ]. It has been shown that poly(ethylene terephthalate) stent surface modification with PLL promotes endothelial cell adhesion and growth [ 21 , 22 ].…”