Nanotech colloquium, 13:00 Friday, 07 Mar 2008, Bldg. 344 Aud. 125

Nanofluidic Devices for Biological and Energy Applications

Sumita Pennathur

University of California, Santa Barbara

Abstract: 

While the challenges and advantages of micro-scale bioanalysis and energy systems are well known, those of systems incorporating nano-scale features have only recently begun to be recognized.   In this talk, we will introduce the concept of using nanofluidic devices for both biological and energy applications, focusing on the unique physics inherent to nanoscale dimensions.  First, we will discuss electrokinetic transport in nanoscale channels, since this transport facilitates control and separation of ionic species.  In nanometer electrokinetic systems, the electric double layer thickness is comparable to channel dimensions, and this results in nonuniform velocity profiles and strong electric fields transverse to the flow. We report continuum-theory-based analytical and numerical studies of nanofluidic electrophoretic transport as well as experimental validation of these models.  One such advantage of this technique is the capability to perform novel separations and hybridizations of biomolecules.  We show example applications for free-solution (gel-free) DNA electrophoresis in nanochannels, including data of size dependant mobilities for 10-100 bp DNA.  We also report experimental results demonstrating on-chip oligonucleotide hybridization coupled with free-solution separation of hybridized DNA from single-stranded DNA. Finally, we report a novel energy application, using streaming currents from pressure-driven nanofluidic flow to generate energy for portable electronic devices.