Rapid, sequence-specific detection of unpurified PCR amplicons via a reusable, electrochemical sensor

Authors

• Rebecca Lai, University of Nebraska - LincolnFollow
• Eric T. Hagally, University of California, Santa Barbara, CA
• Sang-Ho Lee, University of California, Santa Barbara, CA
• H. T. Soh, University of California, Santa Barbara, CA
• Kevin W. Plaxco, University of California, Santa Barbara, CA
• Alan J. Heeger, University of California, Santa Barbara, CA

Document Type

Article

Date of this Version

March 2006

Comments

Published in Proceedings of the National Academy of Sciences U.S.A. 103:11 (March 14, 2006), pp. 4017-4021; doi 10.1073/pnas.0511325103 Copyright © 2006 National Academy of Sciences U.S.A. Used by permission.

Abstract

We report an electrochemical method for the sequence-specific detection of unpurified amplification products of the gyrB gene of Salmonella typhimurium. Using an asymmetric PCR and the electrochemical E-DNA detection scheme, single-stranded amplicons were produced from as few as 90 gene copies and, without subsequent purification, rapidly identified. The detection is specific; the sensor does not respond when challenged with control oligonucleotides based on the gyrB genes of either Escherichia coli or various Shigella species. In contrast to existing sequence-specific optical- and capillary electrophoresis- based detection methods, the E-DNA sensor is fully electronic and requires neither cumbersome, expensive optics nor high voltage power supplies. Given these advantages, E-DNA sensors appear well suited for implementation in portable PCR microdevices directed at, for example, the rapid detection of pathogens.