title: Chemical and biological sensing applications based on graphene field-effect transistors.
abstract: Chemical and biological sensors based on graphene field-effect transistors (G-FETs) were investigated. A single-layer of graphene was prepared by mechanical cleavage of natural graphite. The G-FETs were driven by a reference-gate operating in buffer solution, and exhibited very good transport characteristics. The G-FETs detected the pH value of the solution with high precision. The Dirac point shifted in the positive direction with increasing pH of the solution. The detection limit (signal/noise=3) for measuring changes in the pH of the solution was estimated to be 0.025, indicating the high sensitivity of the G-FETs. Moreover, the devices electrically detected proteins with different charge types. The drain current decreased (increased) when positively (negatively) charged proteins were added to the solution. These results indicate that the G-FETs are among the most suitable candidates for FET-based chemical and biological sensors.
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan. ohno@sanken.osaka-u.ac.jp
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Ohno
authors.forename: Kenzo
authors.initials: K
authors.lastname: Maehashi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D006108:Graphite; D006863:Hydrogen-Ion Concentration; D055767:Immobilized Proteins; D057230:Limit of Detection; D055616:Microtechnology; D012825:Silicon; D014173:Transistors, Electronic
chemical_list: D055767:Immobilized Proteins; D006108:Graphite; D012825:Silicon