Carbon Nanofiber-Based Electrode Interface to Microbial Biofilms
T. E. McKnight, A.V. Melechko, M.A. Guillorn, V.I. Merkulov, J.T. Fleming, D. Hensley, E. Hullander, J. McPherson, D. Nivens, G.S. Sayler, D.H. Lowndes, M. L. Simpson
Oak Ridge National Laboratory - Molecular Scale Engineering Nanoscale Technologies, US
Keywords: nanofiber, electrochemistry, biofilm, gene regulation, biosensor
We report on the integration of bacterial biofilms with carbon nanofiber-based electrochemical systems to provide a robust biosensor platform. Biofilms are robust, self-packaged communities of whole cells that have attracted much attention due to their ubiquity, their resilence, and their impact upon industrial, environmental, and medical processes. In this effort, an interdigitated electrode system was implemented to interface to the engineered cells of a biofilm matrix. The interdigitated electrode array featured 40, individually-addressable, electrodes with each 2 mm wide element populated with forests of vertically-aligned carbon nanofibers. Carbon nanofibers are self-assembling structures with nanometer-scale tips and micron lengths that may be grown normal to the surface of a substrate in a highly deterministic manner, with control over fiber location, length, diameter, geometry, and even chemical composition. The ability to grow fibers at desired locations and the vertical orientation of fibers above the growth substrate provides unique new approaches to electrochemical sensing systems. The vertical aspect of nanofibers provides basis for interrogation around and within biofilm matrices. We will provide overview of our progress with electrochemical characterization of fibered electrodes, local modulation of oxygen-dependent bioluminescence in lux+ biofilms, and electrical induction of genetic elements within cells of the biofilm matrix.
NSTI Nanotech 2003 Conference Technical Program Abstract