title: Fabrication of Ultrasensitive Field-Effect Transistor DNA Biosensors by a Directional Transfer Technique Based on CVD-Grown Graphene.
abstract: Most graphene field-effect transistor (G-FET) biosensors are fabricated through a routine process, in which graphene is transferred onto a Si/SiO2 substrate and then devices are subsequently produced by micromanufacture processes. However, such a fabrication approach can introduce contamination onto the graphene surface during the lithographic process, resulting in interference for the subsequent biosensing. In this work, we have developed a novel directional transfer technique to fabricate G-FET biosensors based on chemical-vapor-deposition- (CVD-) grown single-layer graphene (SLG) and applied this biosensor for the sensitive detection of DNA. A FET device with six individual array sensors was first fabricated, and SLG obtained by the CVD-growth method was transferred onto the sensor surface in a directional manner. Afterward, peptide nucleic acid (PNA) was covalently immobilized on the graphene surface, and DNA detection was realized by applying specific target DNA to the PNA-functionalized G-FET biosensor. The developed G-FET biosensor was able to detect target DNA at concentrations as low as 10 fM, which is 1 order of magnitude lower than those reported in a previous work. In addition, the biosensor was capable of distinguishing the complementary DNA from one-base-mismatched DNA and noncomplementary DNA. The directional transfer technique for the fabrication of G-FET biosensors is simple, and the as-constructed G-FET DNA biosensor shows ultrasensitivity and high specificity, indicating its potential application in disease diagnostics as a point-of-care tool.
authors.forename: Chao
authors.initials: C
authors.lastname: Zheng
authors.affiliation: ‡Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, P.R. China.
authors.forename: Le
authors.initials: L
authors.lastname: Huang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Zhongyue
authors.initials: Z
authors.lastname: Sun
authors.affiliation: ‡Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, P.R. China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Guo-Jun
authors.initials: GJ
authors.lastname: Zhang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003300:Copper / Q000737:chemistry; D004247:DNA / Q000032:analysis*; D006108:Graphite / Q000737:chemistry*; D061925:Immobilized Nucleic Acids / Q000737:chemistry; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization; D020135:Peptide Nucleic Acids / Q000737:chemistry; D019095:Point-of-Care Systems; D012822:Silicon Dioxide / Q000737:chemistry*; D014173:Transistors, Electronic
chemical_list: D061925:Immobilized Nucleic Acids; D020135:Peptide Nucleic Acids; D012822:Silicon Dioxide; D006108:Graphite; D003300:Copper; D004247:DNA
keywords: detection; directional transfer technique; field-effect transistor biosensor; graphene; peptide nucleic acid-DNA hybridization