Ultra-sensitive label-free electrical detection of proteins by field-effect transistor based on chemically derived graphene

N.-E. Lee, D-J Kim, I.Y. Sohn, J-H Jung, O.J. Yoon, J-S Park
Sungkyunkwan University, KR

Keywords: reduced graphene oxide, field-effect transistor, biosensor, immunosensing, label-free detection

Summary:

Here, we present scalable and facile fabrication of R-GO (Reduced Graphene Oxide) FET with the capability of label-free, ultrasensitive electrical detection of biomarkers of prostate cancer and protective antigen of bacillus anthracis in which the ultrathin R-GO channel was formed by a uniform self-assembly of two-dimensional R-GO nanosheets on aminated substrate and followed by immobilization of receptor molecules of antibody and aptamer. Sensing mechanism with kinetics study will be discussed in detail. Sensing analyses of R-GO FET showed the highly precise and linear shift in the Dirac point with the analyte concentration and fM detection limit with a wide dynamic range. Amenability of solution-based scalable fabrication and extremely high performance may enable R-GO FET device as a versatile multiplexed diagnostic biosensor for disease biomarkers.