Wrinkled PDMS-Based Graphene Field Effect Transistor Biosensor

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