Bio
Shanshan Cheng, received the master degree and Ph.D. degree in engineering both from Waseda University, Japan in 2012 and 2015, respectively. Currently, she is an associate professor in School of Science at Tianjin University. She is working in Tianjin Key Laboratory of Molecular Optoelectronic Science. Her current research interests are electrochemical nanotechnology, organic field effect device and interfaces for biosensing and biomedical applications.

Talk
Graphene, an atom-thick 2D carbon material, was used in biosensing applications because of its excellent physical and chemical properties, such as high intrinsic carrier mobility, direct interaction with molecules, large surface areas, and low intrinsic noise. Together with the FET biosensor advantages of being label-free, fast, sensitive, selective, and low cost and possessing on-site detection and a small sample volume consumption, the graphene-based field-effect transistor (GFET) biosensor has been paid attractive attention for cancer diagnosis and virus screening. Previously, direction immobilization of DNA probes on a GFET channel surface for sensitive nucleic acid detection was reported by our group and others. The limit of detection of 10 fM for miRNAs was achieved; however, it still needs to be improved further to fulfil the actual requirements. To improve the performance of GFET biosensors, channel surface functionalization of GFET becomes crucial. Different strategies were reported to understand the sensing mechanisms and improve the sensing performances, such as Au nanoparticles (AuNPs), 1-pyrenebutyric acid succinimidyl ester (PBASE), and so on. We developed a new multi-functional graphene FET with a PLL-functionalized channel (PGFET) biosensor integrated with a microfluidic structure, in short a PGFET biosensor, for ultrasensitive, specific, rapid detection of breast cancer miRNAs and SARS-CoV-2 RNAs, as shown in Figure 1. This is the first proof of concept of breast cancer miRNA and SARS-CoV-2 RNA detection using a PGFET biosensor, which achieves a detection limit of 1fM within 20 min using 2 μL samples, and wide dynamic detection of five orders magnitudes. The performance enhancement mechanism of PGFET biosensors was studied based on electrical sensing model and experimental results. The detection of breast cancer serum samples and simulated SARS-CoV-2 samples demonstrated their practical application capabilities.

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Lin Han received her B.S. in physics from Shandong University, Ji’nan, China in 2003, M.S. in Microelectronics from Tsinghua University, Beijing, China in 2006, and Ph.D. degree in Electrical engineering from Princeton University, NJ, USA in 2011. From 2011 to 2015, she was a postdoc and then promoted to an associated research scientist in Biomedical Engineering at Yale University. From 2015 to 2016, she worked as a principal scientist in Isoplexis company. Since 2016, She has been a Full Professor with the Institute of Marine Science and Technology, Shandong University, Ji’nan, China. Her research interests include biosensors using transistors, SERS, fluorescence, and electrochemical sensing modes, single-cell analysis technologies, flexible electronics, and their applications in human health monitoring, precision diagnosis and therapy of serious diseases, and marine environmental monitoring.

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Tetsuya Osaka is a professor in the Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Tokyo, Japan, a position he has held since 1986. He currently serves as Director of Institute for Nanoscience and Nanotechnology, Waseda University. His recent work is focused on “electrochemical nanotechnology”, including electro- and electroless-deposition/surface finishing, electronic packaging materials, magnetic storage and energy storage devices, and chemical- and bio-sensors.