An electrochemical supersandwich assay for sensitive and selective DNA detection in complex matrices.
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ABSTRACT:
SUBMITTER: Xia F
PROVIDER: S-EPMC3082473 | biostudies-literature | 2010 Oct
REPOSITORIES: biostudies-literature
Publications
An electrochemical supersandwich assay for sensitive and selective DNA detection in complex matrices.
Xia Fan F White Ryan J RJ Zuo Xiaolei X Patterson Adriana A Xiao Yi Y Kang Di D Gong Xiong X Plaxco Kevin W KW Heeger Alan J AJ
Journal of the American Chemical Society 20101001 41
In a traditional sandwich assay, a DNA target hybridizes to a single copy of the signal probe. Here we employ a modified signal probe containing a methylene blue (a redox moiety) label and a "sticky end." When a DNA target hybridizes this signal probe, the sticky end remains free to hybridize another target leading to the creation of a supersandwich structure containing multiple labels. This leads to large signal amplification upon monitoring by voltammetry. ...[more]
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