Gold Nanowire Based Electrical DNA Detection Using Rolling Circle Amplification
2014 (English)In: ACS Nano, ISSN 1936-0851, Vol. 8, no 2, 1147-1153 p.Article in journal (Refereed) Published
We present an electrical sensor that uses rolling circle amplification (RCA) of DNA to stretch across the gap between two electrodes, interact with metal nanoparticle seeds to generate an electrically conductive nanowire, and produce electrical signals upon detection of specific target DNA sequences. RCA is a highly specific molecular detection mechanism based on DNA probe circularization. With this technique, long single-stranded DNA with simple repetitive sequences are produced. Here we show that stretched RCA products can be metalized using silver or gold solutions to form metal wires. Upon metallization, the resistance drops from T Omega to k Omega for silver and to Omega for gold. Metallization is seeded by gold nanoparticles aligned along the single-stranded DNA product through hybridization of functionalized oligonucleotides. We show that combining RCA with electrical DNA detection produces results in readout with very high signal-to-noise ratio, an essential feature for sensitive and specific detection assays. Finally, we demonstrate detection of 10 ng of Escherichia coli genomic DNA using the sensor concept.
Place, publisher, year, edition, pages
2014. Vol. 8, no 2, 1147-1153 p.
gold nanoparticles, rolling circle amplification, nanoelectronics, gold conjugation, metal enhancement
Nano Technology Materials Engineering
IdentifiersURN: urn:nbn:se:su:diva-102481DOI: 10.1021/nn4058825ISI: 000332059200008OAI: oai:DiVA.org:su-102481DiVA: diva2:710549
FunderVinnovaSwedish Research CouncilEU, FP7, Seventh Framework Programme, 259796
Another Funading Agency:
Uppsala University2014-04-072014-04-072014-04-09Bibliographically approved