A reagentless signal-on architecture for electronic, aptamer-based sensors via target-induced strand displacement.
Thrombin binding stabilizes the alternative G-quadruplex conformation of the aptamer, liberating the methylene blue (MB)-tagged oligonucleotide to produce a flexible, single-stranded DNA element. This allows the MB tag to collide with the gold electrode surface, producing a readily detectable Faradaic current at thrombin concentrations as low as approximately 3 nM.
Xiao
Yi
Y
Department of Physics, Institute for Polymers and Organic Solids, Program in BioMolecular Science and Engineering, University of California, Santa Barbara, California 93106, USA.
Piorek
Brian D
BD
Plaxco
Kevin W
KW
Heeger
Alan J
AJ
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry; D013917:Thrombin / Q000737:chemistry
D052157:Aptamers, Nucleotide; D006046:Gold; D004247:DNA; D013917:Thrombin