Nanomaterials for Nucleic Acid Sensing
Nagler Laboratory
Biological sciences currently use microarrays to address scientific questions and provide diagnostic information regarding genomics. There are limitations of high density screening of DNA for genomic or diagnostic purposes utilizing single-use microarrays on glass slides or nitrocellulose membranes. This project is developing a reusable and quantitative device to detect and quantify nucleic acids for biological study. The principle is based on an electrical circuit that incorporates silica nanosprings coated with short, gene specific DNA sequences. Nanosprings have an extremely large surface area, which can be functionalized to attach biological molecules. DNA molecules will be attached to the nanosprings and hybridization of complementary DNA sequences will cause a change in the resistance or impedance of the circuit. Electrical detection is more sensitive, quantifiable, and repeatable than other existing technologies (e.g., spectroscopic detection) and can be interfaced to electronic hardware for measuring, storing, and integrating the information from multiple sensing events. We will employ this device for sensitive and reproducible DNA detection required for genomic research. Ultimately, many of these devices each unique for a specific gene will be arrayed on a planar platform (i.e., a nanoarray). Analogous to current microarray technology, each device would simultaneously detect all the complementary gene-specific nucleic acids present in a biological sample. However, unlike a microarray, a nanoarray would provide precise quantitative data for each gene present and could be re-used multiple times.
Research Team:D. Eric Aston, Department of Chemical Engineering
Josh Branen, Biosensor and Nanotechnology Applications Laboratory, UI Research Park
Larry Branen, Biosensor and Nanotechnology Applications Laboratory, UI Research Park
Giancarlo Corti, Departments of Mechanical Engineering and Physics
David N. McIlroy, Department of Physics
James J. Nagler, Department of Biological Sciences
These photographs are from a scanning electron microscope showing a device comprised of a two terminal electrical circuit incorporating silica nanosprings (left). On the right is an enlarged view of the edge of the gap showing the nanospring mat that spans the two gold electrodes (and completes the circuit).
