title: DNA-PEG-DNA triblock macromolecules for reagentless DNA detection.
abstract: The sandwich assay is the most common design for electrochemical DNA sensors. This assay consists of three individual DNA components: an immobilized capture strand, a target strand, and a probe strand containing a redox-active reporter group. We report a simplified DNA assay where two strands of ssDNA, the capture and probe strands, are linked together via a flexible poly(ethylene glycol) (PEG) spacer forming an ABA triblock macromolecule. We have developed an electrochemical assay where the detection signal arises as a consequence of a large structural change induced upon hybridization with target DNA. In this system, the DNA-PEG-DNA macromolecule folds or wraps around the target DNA, bringing the ferrocene probe in close proximity to the electrode, affording an electrochemical response.
authors.affiliation: Departments of Biomedical Engineering and Chemistry, Metcalf Center for Science and Engineering, Boston University, Boston, MA 02215, USA.
authors.forename: Chad E
authors.initials: CE
authors.lastname: Immoos
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Lee
authors.forename: Mark W
authors.initials: MW
authors.lastname: Grinstaff
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry; D046911:Macromolecular Substances; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D009841:Oligonucleotides; D011092:Polyethylene Glycols; D006046:Gold; D004247:DNA