Over the past four years, my research group has been focused on the development of conducting polymer nanowire-based sensing devices using a template-free electrochemical approach. Following on from these studies, our group has been able to miniaturize the fabrication of CPNEJs in the microfluidic systems. Obviously, there are key advantages to fabricating CPNEJs within a microfluidic device, including: (a) the introduction and delivery of small amounts of precursor monomers are highly controllable and enable the rapid exchange of nanoliter-level solutions for large-scale fabrication; (b) the turbulence-free environment within a microchannel helps the formation of well defined nanowires during the electropolymerization process; and (c) once the CPNEJs are fabricated, the entire device is ready for use as a fully functional sensor, equipped with integrated microchannel for handling nanoliter-level analytes. We envision that these research efforts will open up new possibilities for the fabrication of high-density chemical and biological sensors.
Lab talk
Oct 26, 2007
Conducting polymer nanowires
Recently, a joint research effort led by Professor Nitin Padture at the Ohio State University and myself at UCLA has demonstrated an efficient, labor-free, site-specific and scalable approach to the production of high quality and individually addressable conducting polymer nanowire electrode junctions (CPNEJs) in a parallel-oriented array. We were able to introduce polyaniline, polypyrrole and poly(EDOT) nanowires, with uniform diameters (60–150 nm), into the CPNEJs in a precise manner by performing sequential electrochemical polymerizations from their respective monomer solutions. It is worthwhile to note that under the very gentle electrochemical conditions, the conducting polymer chains are allowed to self-organize in the polymer nanowires and form novel polycrystalline structures.
About the author
Hsian-Rong Tseng has been an assistant professor at the Department of Molecular & Medical Pharmacology and the Crump Institute for Molecular Imaging in the David Geffen School of Medicine at UCLA since 2003. Prior to that, he obtained his PhD degree (1993–1998) from National Taiwan University with a major in organic chemistry and did his postdoctoral training (2000–2003) at the UCLA Department of Chemistry and Biochemistry. Currently, his research interests are the development of microfluidics-based technology platforms and the utilization of these technology platforms across the fields of nanostructured materials, molecular imaging and cancer biology.