title: Label-free detection of DNA hybridization using carbon nanotube network field-effect transistors.
abstract: We report carbon nanotube network field-effect transistors (NTNFETs) that function as selective detectors of DNA immobilization and hybridization. NTNFETs with immobilized synthetic oligonucleotides have been shown to specifically recognize target DNA sequences, including H63D single-nucleotide polymorphism (SNP) discrimination in the HFE gene, responsible for hereditary hemochromatosis. The electronic responses of NTNFETs upon single-stranded DNA immobilization and subsequent DNA hybridization events were confirmed by using fluorescence-labeled oligonucleotides and then were further explored for label-free DNA detection at picomolar to micromolar concentrations. We have also observed a strong effect of DNA counterions on the electronic response, thus suggesting a charge-based mechanism of DNA detection using NTNFET devices. Implementation of label-free electronic detection assays using NTNFETs constitutes an important step toward low-cost, low-complexity, highly sensitive and accurate molecular diagnostics.
authors.affiliation: Nanomix, Inc., Emeryville, CA 94608, USA. astar@pitt.edu
authors.forename: Alexander
authors.initials: A
authors.lastname: Star
authors.forename: Eugene
authors.initials: E
authors.lastname: Tu
authors.forename: Joseph
authors.initials: J
authors.lastname: Niemann
authors.forename: Jean-Christophe P
authors.initials: JC
authors.lastname: Gabriel
authors.forename: C Steve
authors.initials: CS
authors.lastname: Joiner
authors.forename: Christian
authors.initials: C
authors.lastname: Valcke
mesh_terms: D000483:Alleles; D020137:Base Pair Mismatch; D001483:Base Sequence; D004247:DNA / Q000737:chemistry / Q000235:genetics*; D004277:DNA, Single-Stranded / Q000235:genetics; D004566:Electrodes; D004583:Electrons; D006432:Hemochromatosis / Q000235:genetics; D006801:Humans; D007477:Ions; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation; D036103:Nanotechnology; D037742:Nanotubes, Carbon; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D013997:Time Factors; D014173:Transistors, Electronic
chemical_list: D004277:DNA, Single-Stranded; D007477:Ions; D037742:Nanotubes, Carbon; D009841:Oligonucleotides; D004247:DNA