Effects of nanopatterned RGD peptide layer on electrochemical detection of neural cell chip

The cell-based chip is becoming a popular tool for monitoring living cell viability under various conditions. In this study, several biomaterials, such as synthetic Cys-(Arg-Gly-Asp)4 (C(RGD)4), Arg-Gly-Asp-Multi Armed-Cys (RGD-MAP-C) peptide, and poly-l-lysine (PLL) nano-dots were fabricated on the gold surface of a neural cell chip. The material-dependent effects both on electrochemical signal detection in neural cells and on cellular adhesion were analyzed. The nano-dot structures were fabricated through a nanoporous alumina mask, and the structural formations were confirmed by scanning electron microscopy (SEM). PC12 cells were allowed to attach on several peptide nanopatterned surfaces, and electrochemical tools were applied to neural cells attached on the chip surface. The RGD-MAP-C peptide nanopatterned surface provided the strongest voltammetric signals when the cell was exposed to cyclic voltammetry (CV) and differential pulse voltammetry (DPV) after 48 h of incubation, which may largely be due to an enhanced affinity between cells and the Au surface. Chemical toxicity assessments were conducted in the fabricated cell chip, and they showed negative correlations between neural cell viability and the concentration of chemicals. In conclusion, a nanopatterned RGD-MAP-C layer improved cell-binding affinity to Au substrates and showed sufficient sensitivity for electrochemical detection of cell viability.