AVS 52nd International Symposium
    Nanometer-Scale Science and Technology Monday Sessions
       Session NS2-MoM

Paper NS2-MoM3
Metal, and Conducting Polymer Nanowires for Gas and Biomolecule Sensing

Monday, October 31, 2005, 9:00 am, Room 210

Session: Nanowires
Presenter: M. Yun, University of Pittsburgh
Authors: M. Yun, University of Pittsburgh
C. Lee, Jet Propulsion Laboratory
R. Vasquez, Jet Propulsion Laboratory
N. Myung, University of California at Riverside
J. Wang, University of California at Los Angeles
H. Monbouquette, University of California at Los Angeles
A. Mulchandani, University of California at Riverside
Correspondent: Click to Email
Single Palladium (Pd), Polyaniline(PANI), and Polypyrrole(PPY) nanowires from 70 nm to 300 nm in diameter and up to 7 µ in length have been synthesized using e-beam lithography and electrodeposition. This fabrication method enables the use of various materials for single nanowire sensors, such as polymers, metal oxides, and semiconductors. These fabricated Pd nanowires are used to sense hydrogen gases and have achieved a sensitivity of 0.02% H2. In addition, we have observed that the resistance of the 200 nm wide avidin-functionalized PPY nanowires increased rapidly to a constant value upon addition of 1 nM of the biotin-DNA conjugate and the resistance increased with increasing concentrations up to 100 nM. At last, we will present that arrays of nanowires with controlled dimensions are fabricated on substrates, optionally as integral parts of multilayer structures, by means of a high-yield process based on ion milling on steps (IMOS). To demonstrate the utility of functionalized IMOS nanowires as sensors, we have successfully demonstrated Pt nanowire array and precisely assembled glucose oxide (GOx) on Pt nanowire array by co-deposition with electropolymerized PPY. A mixture of GOx and pyrrole is used in PBS solution for electrochemical polymer formation and GOx immobilization. It has been verified by measuring the current sensitivity of 0.3 nA/mM to the glucose with IMOS Pt nanowires.