Wrinkled PDMS-Based\nGraphene Field Effect Transistor\nBiosensor

Real-time cell proliferation assays, incorporating fluorescent\ndyes into cells and bulky optical imaging systems, are the gold standard\nfor cellular analysis at the single-cell level. As components of a\nsimplified and miniaturized system, a conventional field-effect transistor\n(FET)-based platform allows the label-free detection of biomolecules\nby measuring their inherent charge carriers. In this study, we developed\na winkled graphene-based FET (G-FET) to evaluate the process of cell\nproliferation with directional characteristics of myoblast alignment,\ncompared to the conventional imaging approach. Various uniaxially\nwrinkled structures with highly uniform and regular patterns were\nobtained over a millimeter scale channel by tuning the fabrication\nparameters on the wrinkled G-FET through facile fabrication. As a\nresult, it showed that the wrinkled G-FET enhanced the electrical\nsignals during cell growth from in vitro cell culture compared to\nthe flat FET device, giving guidance for cell orientations with sensing\ncapability for cell proliferation. The improvement of sensitivity\nof the wrinkled G-FET was verified through various concentrations\nof the ion. Through the facile fabrication process and label-free\nelectrical detection, our sensing platform will support bringing complex\nlab-based diagnostic assays to small-footprint detection devices for\nefficient cell proliferation sensing and the analysis of cell directionality.