Label‐Free Analysis of Thrombin or Hg²⁺ Ions by Nucleic Acid‐Functionalized Graphene Oxide Matrices Assembled on Field‐Effect Transistors

Graphene oxide (GO) is deposited onto the Al 2 O 3 gates of field‐effect transistor devices to yield a functional matrix for the sensing of thrombin or Hg 2+ ions. The deposition of an aptamer subunit against thrombin or a tailored nucleic acid with appropriate T mismatches on the GO, yield active surfaces for the analysis of thrombin or Hg 2+ ions. The desorption of the aptamer‐subunit from GO, through the formation of the aptamer‐thrombin complex, or the desorption of the T–Hg 2+ –T‐bridged duplex DNA alter the gate potential, thus providing a signal for the sensing events.