Rapid, sequence-specific detection of unpurified PCR amplicons via a reusable, electrochemical sensor.
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.
Center for Polymers and Organic Solids, Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA.
Rebecca Y
RY
Lai
Eric T
ET
Lagally
Sang-Ho
SH
Lee
H T
HT
Soh
Kevin W
KW
Plaxco
Alan J
AJ
Heeger
D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D027081:DNA Gyrase / Q000235:genetics; D015342:DNA Probes / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004563:Electrochemistry; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D021141:Nucleic Acid Amplification Techniques; D009690:Nucleic Acid Conformation; D016133:Polymerase Chain Reaction / Q000379:methods*; D012486:Salmonella typhimurium / Q000235:genetics; D012763:Shigella flexneri / Q000235:genetics; D012764:Shigella sonnei / Q000235:genetics; D013045:Species Specificity
D015342:DNA Probes; D004269:DNA, Bacterial; D027081:DNA Gyrase