Conformationally gated electrochemical gene detection.
The synthesis and characterization of a 26-base DNA hairpin containing both a redox-active reporter (ferrocene) and terminal thiol functionality for electrochemical gene detection is described. This electrochemical DNA sensor exploits electron-transfer dynamics that alter as a consequence of a large structural rearrangement (hairpin-to-duplex) induced by hybridization of the target DNA sequence. Melting temperature and circular dichroism studies confirm that the 26-mer DNA forms a hairpin structure in the absence of target DNA. The loop region of the DNA hairpin is shown to form a stable duplex in the presence of complementary single-stranded DNA. Atomic force microscopy and ellipsometry experiments of immobilized self-assembled DNA monolayers suggest that hybridization with complementary DNA affords a conformational change that alters the electrochemical response.
Department of Chemistry, Duke University, Durham, NC 27708, USA.
Chad E
CE
Immoos
Stephen J
SJ
Lee
Mark W
MW
Grinstaff
D001483:Base Sequence; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D018625:Microscopy, Atomic Force; D010084:Oxidation-Reduction
D004247:DNA