title: Ultrasensitive flexible graphene based field-effect transistor (FET)-type bioelectronic nose.
abstract: Rapid and precise discrimination of various odorants is vital to fabricating enhanced sensing devices in the fields of disease diagnostics, food safety, and environmental monitoring. Here, we demonstrate an ultrasensitive and flexible field-effect transistor (FET) olfactory system, namely, a bioelectronic nose (B-nose), based on plasma-treated bilayer graphene conjugated with an olfactory receptor. The stable p- and n-type behaviors from modified bilayer graphene (MBLG) took place after controlled oxygen and ammonia plasma treatments. It was integrated with human olfactory receptors 2AG1 (hOR2AG1: OR), leading to the formation of the liquid-ion gated FET-type platform. ORs bind to the particular odorant amyl butyrate (AB), and their interactions are specific and selective. The B-noses behave as flexible and transparent sensing devices and can recognize a target odorant with single-carbon-atom resolution. The B-noses are ultrasensitive and highly selective toward AB. The minimum detection limit (MDL) is as low as 0.04 fM (10(-15); signal-to-noise: 4.2), and the equilibrium constants of OR-oxygen plasma-treated graphene (OR-OG) and ammonia plasma-treated graphene (-NG) are ca. 3.44 × 10(14) and 1.47 × 10(14) M(-1), respectively. Additionally, the B-noses have long-term stability and excellent mechanical bending durability in flexible systems.
authors.affiliation: World Class University Program of Chemical Convergence for Energy & Environment, School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, Korea.
authors.forename: Seon Joo
authors.initials: SJ
authors.lastname: Park
authors.forename: Oh Seok
authors.initials: OS
authors.lastname: Kwon
authors.forename: Sang Hun
authors.initials: SH
authors.lastname: Lee
authors.forename: Hyun Seok
authors.initials: HS
authors.lastname: Song
authors.forename: Tai Hyun
authors.initials: TH
authors.lastname: Park
authors.forename: Jyongsik
authors.initials: J
authors.lastname: Jang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000706:statistics & numerical data; D002087:Butyrates / Q000032:analysis; D006108:Graphite; D006801:Humans; D036103:Nanotechnology; D009666:Nose; D009812:Odorants / Q000032:analysis*; D018035:Receptors, Odorant / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D014173:Transistors, Electronic
chemical_list: D002087:Butyrates; C514887:OR2AG1 protein, human; D018035:Receptors, Odorant; D011994:Recombinant Proteins; C046390:n-amyl butyrate; D006108:Graphite