title: DNA-decorated carbon nanotubes for chemical sensing.
abstract: We demonstrate a new, versatile class of nanoscale chemical sensors based on single-stranded DNA (ss-DNA) as the chemical recognition site and single-walled carbon nanotube field effect transistors (swCN-FETs) as the electronic read-out component. swCN-FETs with a nanoscale coating of ss-DNA respond to gas odors that do not cause a detectable conductivity change in bare devices. Responses of ss-DNA/swCN-FETs differ in sign and magnitude for different gases and can be tuned by choosing the base sequence of the ss-DNA. ss-DNA/swCN-FET sensors detect a variety of odors, with rapid response and recovery times on the scale of seconds. The sensor surface is self-regenerating: samples maintain a constant response with no need for sensor refreshing through at least 50 gas exposure cycles. This remarkable set of attributes makes sensors based on ss-DNA decorated nanotubes very promising for "electronic nose" and "electronic tongue" applications ranging from homeland security to disease diagnosis.
authors.affiliation: Department of Physics and Astronomy and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Cristian
authors.initials: C
authors.lastname: Staii
authors.forename: Alan T
authors.initials: AT
authors.lastname: Johnson
authors.forename: Michelle
authors.initials: M
authors.lastname: Chen
authors.forename: Alan
authors.initials: A
authors.lastname: Gelperin
mesh_terms: D001483:Base Sequence; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000235:genetics; D004563:Electrochemistry; D005740:Gases / Q000032:analysis; D018625:Microscopy, Atomic Force; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry; D009812:Odorants / Q000032:analysis
chemical_list: D004277:DNA, Single-Stranded; D005740:Gases; D037742:Nanotubes, Carbon