TY - JOUR
T1 - Amplified biosensing using the horseradish peroxidase-mimicking DNAzyme as an electrocatalyst
AU - Pelossof, Gilad
AU - Tel-Vered, Ran
AU - Elbaz, Johann
AU - Willner, Itamar
PY - 2010/6/1
Y1 - 2010/6/1
N2 - The hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme is assembled on Au electrodes. It reveals bioelectrocatalytic properties and electrocatalyzes the reduction of H2O2. The bioelectrocatalytic functions of the hemin/G-quadruplex DNAzyme are used to develop electrochemical sensors that follow the activity of glucose oxidase and biosensors for the detection of DNA or low-molecular-weight substrates (adenosine monophosphate, AMP). Hairpin nucleic structures that include the G-quadruplex sequence in a caged configuration and the nucleic acid sequence complementary to the analyte DNA, or the aptamer sequence for AMP, are immobilized on Au-electrode surfaces. In the presence of the DNA analyte, or AMP, the hairpin structures are opened, and the hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme structures are generated on the electrode surfaces. The bioelectrocatalytic cathodic currents generated by the functionalized electrodes, upon the electrochemical reduction of H2O2, provide a quantitative measure for the detection of the target analytes. The DNA target was analyzed with a detection limit of 1 × 10-12 M, while the detection limit for analyzing AMP was 1 × 10-6 M. Methods to regenerate the sensing surfaces are presented.
AB - The hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme is assembled on Au electrodes. It reveals bioelectrocatalytic properties and electrocatalyzes the reduction of H2O2. The bioelectrocatalytic functions of the hemin/G-quadruplex DNAzyme are used to develop electrochemical sensors that follow the activity of glucose oxidase and biosensors for the detection of DNA or low-molecular-weight substrates (adenosine monophosphate, AMP). Hairpin nucleic structures that include the G-quadruplex sequence in a caged configuration and the nucleic acid sequence complementary to the analyte DNA, or the aptamer sequence for AMP, are immobilized on Au-electrode surfaces. In the presence of the DNA analyte, or AMP, the hairpin structures are opened, and the hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme structures are generated on the electrode surfaces. The bioelectrocatalytic cathodic currents generated by the functionalized electrodes, upon the electrochemical reduction of H2O2, provide a quantitative measure for the detection of the target analytes. The DNA target was analyzed with a detection limit of 1 × 10-12 M, while the detection limit for analyzing AMP was 1 × 10-6 M. Methods to regenerate the sensing surfaces are presented.
UR - http://www.scopus.com/inward/record.url?scp=77952978237&partnerID=8YFLogxK
U2 - 10.1021/ac100095u
DO - 10.1021/ac100095u
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C2 - 20441165
AN - SCOPUS:77952978237
SN - 0003-2700
VL - 82
SP - 4396
EP - 4402
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 11
ER -