High density gold nanostructure composites for precise electrochemical detection of human embryonic stem cells in cell mixture

Precise detection of undifferentiated human pluripotent stem cells (hPSCs) and their entire subsequent elimination are incredibly important in preventing teratoma formations after transplantation. Recently, electrochemical sensing platforms have demonstrated immense potential as a new tool to detect remaining hPSCs in label-free and non-destructive manner. Nevertheless, one of the critical huddles of this electrochemical sensing approach is its low sensitivity since even low concentrations of remaining hPSCs were reported to form teratoma once transplanted. To address this issue, in this study, we report an engineering-based approach to improve the sensitivity of electrochemical sensing platform for hPSC detection. By optimizing the density of gold nanostructure and the matrigel concentration to improve both electro-catalytic property and biocompatibility, the sensitivity of the developed platform toward hESCs detection could reach 12,500 cells/chip, which is close to the known critical concentration of hPSCs ((similar to)10,000 cells) that induce teratoma formation in vivo. Remarkably, the electrochemical signals were not detectable from other types of stem cell-derived endothelial cells (CB-EPCs) even at high concentrations of CB-EPCs (40,000 cells/chip), proving the high selectivity of the developed platform toward hPSC detection. Hence, the developed platform could be highly useful to solve the safety issues that are related with clinical application of hPSC-derived cells.