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PubMed · 16213156

Electrochemical molecular analysis without nucleic acid amplification.

Vincent Gau·Shu-Ching Ma·Hua Wang·Joni Tsukuda·John Kibler·David A Haake
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Abstract

Electrochemical biosensors have revolutionized glucose monitoring but have not yet fulfilled their promise of a low cost, direct detection replacement for genetic amplification tests such as PCR [K. Kerman, M. Kobayashi, E. Tamiya, Recent trends in electrochemical DNA biosensor technology, Meas. Sci. Technol. 15 (2004) R1-R11; A. Chaubey, B.D. Malhotra, Mediated biosensors. Biosens. Bioelectron. 17 (6-7) (2002) 441-456]. It has been anticipated that the integration of nanoscale chemical structures such as self-assembled monolayers with electrochemical biosensors would increase sensitivity by decreasing inherent system noise. We have designed a novel biosensing approach incorporating such integration and achieved rapid, ultra-low concentration sensitivities without target amplification. Raw samples are mixed with lysis buffer to allow hybridization of nucleic acid targets with anchor and signal probes before immobilizing a signaling enzyme proximate to the biosensor surface. A bias potential is subsequently applied and the secondary byproduct of a cyclic peroxidase reaction measured. Further studies have demonstrated the application of our approach in protein, clinical chemistry, and ionic assays.

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Biosensing TechniquesDNAElectrochemistryImmunoassayNucleic Acid Amplification TechniquesJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tReview

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Vincent Gau, Shu-Ching Ma, Hua Wang, Joni Tsukuda, John Kibler, David A Haake. 2005-10-04. Electrochemical molecular analysis without nucleic acid amplification.. https://doi.org/10.1016/j.ymeth.2005.05.008

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