CAREER: DNA Transport Through Carbon Nanotubes

Suny At Binghamton, Binghamton NY

Investigators

Abstract

DNA Transport Through Carbon Nanotubes Non-technical Summary This CAREER Award by the Biomaterials program in the Division of Materials Research is to study the passage of molecules through small pores. The passage of molecules through small pores or structures plays a key role in many biological processes. Biological molecules regularly cross through pores in nuclear and cellular membranes to effect cell activity. This translocation process plays an essential role in many areas of biotechnology, like drug delivery and assembling recombinant DNA. This process can be studied experimentally by observing the rate that DNA molecules travel through well-defined nano-structures under the application of an electric field. There is still considerable debate concerning the fundamental physical processes that govern this process. It is envisioned that the results obtained from these experiments will inform the fabrication of future devices for the separation, manipulation, and potential sequencing of nucleic acids. The PI will measure the rate at which single stranded DNA molecules are transported through individual carbon nanotubes, both optically and electrically. In parallel to the research portion of this project the PI will use the concepts of polymer physics and nanofabrication as models in outreach efforts aimed toward increasing participation in physics by different groups of elementary, college, and graduate students. The proposed activities would significantly improve the physics education in local elementary schools in high-need rural areas of upstate New York. The method for integrating the educational plan into the research program relies on the active participation of undergraduate and graduate students in the PI's laboratory. Much of the science content will be taught using DNA as an example of a model polymer, which is a rich pedagogical tool combining aspects of biology, physics, and material science. The elementary school education will have a focus on microfabrication and biotechnology and their impacts on everyday life. Technical Summary In this project the PI will optically and electrically measure the rate at which single stranded DNA molecules are transported through individual carbon nanotubes, thus aiding in the understanding of the physical mechanisms that govern biomolecule transport through nanopores. The combination of optical detection with electrical detection is required to address fundamental questions about the transport process. Fluorescent DNA molecules will be tracked as they translocate a nanotube while the ionic current through the nanotube is simultaneously measured. The PI will measure capture rates and transit times using semiconducting and metallic carbon nanotubes as a function of applied voltage, DNA concentration, DNA length, and salt concentration. Modulating the charge on the carbon nanotubes will enable the PI to determine the critical role of electroosmosis in the transport process. This approach will also elucidate the dependence of the nanotube chirality and the nanotube surface charge on the DNA transport process. This experimental program will provide a quantitative understanding of biomolecular transport that ties together soft condensed matter physics, chemistry, and biology. In addition to the research portion of this project the PI will implement an integrated education plan that addresses current needs in Binghamton University's undergraduate and graduate curriculum. The components of the educational plan include: (1) a microfabrication module for undergraduate biologists aimed at increasing participation of underrepresented groups in physics; (2) entrepreneurship training for graduate students in the physical sciences; and (3) an outreach program that provides physics demonstrations to local elementary school children.