title: Label-free and reagentless aptamer-based sensors for small molecules.
abstract: A label free, reagentless aptasensor for adenosine is developed on an ISFET device. The separation of an aptamer/nucleic acid duplex by adenosine leads to the aptamer/adenosine complex that alters the gate potential of the ISFET. The sensitivity limit of the device is 5 x 10-5 M. Also, the immobilization of the aptamer/nucleic acid duplex on an Au-electrode and the separation of the duplex by adenosine mono-phosphate (AMP) enable the electrochemical detection of adenosine by faradaic impedance spectroscopy. The separation of the aptamer/nucleic acid duplex by adenosine and the formation of the aptamer/adenosine complex results in a decrease in the interfacial electron-transfer resistance in the presence of [Fe(CN)6]3-/4- as redox active substrate.
authors.affiliation: The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Maya
authors.initials: M
authors.lastname: Zayats
authors.forename: Ye
authors.initials: Y
authors.lastname: Huang
authors.forename: Ron
authors.initials: R
authors.lastname: Gill
authors.forename: Chun-an
authors.initials: CA
authors.lastname: Ma
authors.forename: Itamar
authors.initials: I
authors.lastname: Willner
mesh_terms: D000249:Adenosine Monophosphate / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001483:Base Sequence; D001665:Binding Sites; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003042:Cocaine / Q000032:analysis / Q000737:chemistry; D003568:Cytidine Monophosphate / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D053834:Explosive Agents / Q000032:analysis / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D010084:Oxidation-Reduction
chemical_list: D052157:Aptamers, Nucleotide; D053834:Explosive Agents; D000249:Adenosine Monophosphate; D006046:Gold; D003568:Cytidine Monophosphate; D003042:Cocaine