Nanofluidic Platform for Virus Study

Two weeks ago, Prof Jacobson from Indiana University gave an invited talk at our department. His research focuses on developing microfabricated instrumentation and using this instrumentation to study various chemical and biochemical problems. His group is currently pursuing projects which fall into the areas of (1) microfluidic separations, (2) bacteria based studies, (3) fundamentals of nanofluidics, and (4) nanofluidic sensing. 

In his talk he focused primarily on sensing viruses using nanofluidic devices. Fabrication of nanofluidic device itself is challenging. They fabricate nanochannels which connect two microchannels. Shape (angle) of the nanochannel at microchannel-nanochannel junction shows different physical phenomenon. Nanofluidic systems can be significantly influenced by phenomena such as double layer overlap, surface charge, diffusion, and entropic forces, which are either insignificant or absent in larger microchannels. 


They have studied the characterization of Hepatitis B virus (HBV) capsids by resistive-pulse sensing through single track-etched conical nanopores formed in poly(ethylene terephthalate) membranes. When the virus capsid is allowed to travel through the nanopore, current on the nanopre is monitored. During this event, the conductivity on the nanopore changes because the virus capsid replaces the conductivity solution. This allows to monitor the virus capsid. 


Similar strategies have been used to characterize DNA molecules. DNA molecules are passed through nanochannels and change in current is monitored. When such molecules passe through the pores, there is decrease in current episode.