DNA-CNT nanowire networks for DNA detection.

TitleDNA-CNT nanowire networks for DNA detection.
Publication TypeJournal Article
Year of Publication2011
AuthorsWeizmann, Y, Chenoweth, DM, Swager, TM
JournalJournal of the American Chemical Society
Date Publishedmar
KeywordsCarbon, Carbon: chemistry, DNA, DNA Probes, DNA Probes: chemistry, DNA: analysis, Electric Conductivity, Electron, Humans, Microscopy, Nanotubes, Nanowires, Nanowires: chemistry, Nucleic Acid Hybridization, Nucleic Acid Hybridization: methods, Scanning

The ability to detect biological analytes in a rapid, sensitive, operationally simple, and cost-effective manner will impact human health and safety. Hybrid biocatalyzed-carbon nanotube (CNT) nanowire-based detection methods offer a highly sensitive and specific platform for the fabrication of simple and effective conductometric devices. Here, we report a conductivity-based DNA detection method utilizing carbon nanotube-DNA nanowire devices and oligonucleotide-functionalized enzyme probes. Key to our sensor design is a DNA-linked-CNT wire motif, which forms a network of interrupted carbon nanotube wires connecting two electrodes. Sensing occurs at the DNA junctions linking CNTs, followed by amplification using enzymatic metalization leading to a conductimetric response. The DNA analyte detection limit is 10 fM with the ability to discriminate single, double, and triple base pair mismatches. DNA-CNT nanowires and device sensing gaps were characterized by scanning electron microscopy (SEM) and confocal Raman microscopy, supporting the enhanced conductometric response resulting from nanowire metallization.