Fabrication of ITO/Gold nanoparticle/RGD peptide Composites to Enhance Electrochemical Signals from Human Neural Stem Cells

Gold nanoparticles (GNP) and RGD peptide modified indium tin oxide (ITO) electrode was fabricated to enhance the electrochemical signals from neural stem cells (HB1.F3). Aminopropyltrimethoxylane (APTMS) was selfassembled on ITO electrode surface to immobilze GNP and its topological characteristics were confirmed by scanning electron microscopy (SEM). Thereafter, cysteine containing RGD peptide (RGD-MAP-C) was self-assembled on GNP immobilized surfaces via strong Au-S bond. Cells were seeded on the fabricated surface, and their electrochemical characteristics were analyzed by cyclic voltammetry (CV). As a result, ITO/GNP/RGD peptide composite was found to give highest redox signals compared to the bare ITO, ITO/RGD peptide and ITO/GNP substrate. Finally, the cell proliferation on different substrates were also analyzed by trypan blue assay to verify the effects of ITO/GNP/RGD peptide composites on human neural stem cells. Our newly fabricated substrate can be usefully applied for both electrochemical and optical study of stem cells.