• 文献标题:   Chemical Sensors Generated on Wafer-Scale Epitaxial Graphene for Application to Front-Line Drug Detection
  • 文献类型:   Article
  • 作  者:   KARLSSON M, STRANDQVIST C, JUSSI J, OBERG O, PETERMANN I, ELMLUND L, DUNNE S, FU Y, WANG Q
  • 作者关键词:   epitaxial graphene, sensor, microfluidic, photoactivity, illicit drug, forensic
  • 出版物名称:   SENSORS
  • ISSN:   1424-8220
  • 通讯作者地址:   RISE Res Inst Sweden AB
  • 被引频次:   0
  • DOI:   10.3390/s19102214
  • 出版年:   2019

▎ 摘  要

Generation of large areas of graphene possessing high quality and uniformity will be a critical factor if graphene-based devices/sensors are to be commercialized. In this work, epitaxial graphene on a 2" SiC wafer was used to fabricate sensors for the detection of illicit drugs (amphetamine or cocaine). The main target application is on-site forensic detection where there is a high demand for reliable and cost-efficient tools. The sensors were designed and processed with specially configured metal electrodes on the graphene surface by utilizing a series of anchors where the metal contacts are directly connected on the SiC substrate. This has been shown to improve adhesion of the electrodes and decrease the contact resistance. A microfluidic system was constructed to pump solutions over the defined graphene surface that could then act as a sensor area and react with the target drugs. Several prototypic systems were tested where non-covalent interactions were used to localize the sensing components (antibodies) within the measurement cell. The serendipitous discovery of a wavelength-dependent photoactivity for amphetamine and a range of its chemical analogs, however, limited the general application of these prototypic systems. The experimental results reveal that the drug molecules interact with the graphene in a molecule dependent manner based upon a balance of -stacking interaction of the phenyl ring with graphene (p-doping) and the donation of the amine nitrogens lone pair electrons into the *-system of graphene (n-doping).