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

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.