Electrochemical Approaches to Aptamer-Based Sensing

  • Yi Xiao
  • Kevin W. Plaxco
Part of the Integrated Analytical Systems book series (ANASYS)


Motivated by the potential convenience of electronic detection, a wide range of electrochemical, aptamer-based sensors have been reported since the first was described only in 2005. Although many of these are simply electrochemical, aptamer-based equivalents of traditional immunochemical approaches (e.g., sandwich and competition assays employing electroactive signaling moieties), others exploit the unusual physical properties of aptamers, properties that render them uniquely well suited for application to impedance and folding-based electrochemical sensors. In particular, the ability of electrode-bound aptamers to undergo reversible, binding-induced folding provides a robust, reagentless means of transducing target binding into an electronic signal that is largely impervious to nonspecific signals arising from contaminants. This capability enables the direct detection of specific proteins at physiologically relevant, picomolar concentrations in blood serum and other complex, contaminant-ridden sample matrices.


Methylene Blue Redox Mediator Nonspecific Adsorption Sandwich Assay Electrochemical Aptasensors 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported in part by NIH EB002046, by NSF DMR 0099843, by Lawrence Livermore National Laboratory (URP-06–019), and by the Institute for Collaborative Biotechnologies through grant DAAD19-03-D-0004 from the US Army Research Office.


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Yi Xiao
    • 1
  • Kevin W. Plaxco
    • 2
  1. 1.Department of Physics, Materials Department, Department of Chemistry and BiochemistryUniversity of CaliforniaSanta Barbara
  2. 2.Department of Chemistry and Biochemistry, Interdepartmental program in Biomolecular Science and EngineeringUniversity of CaliforniaSanta Barbara

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