• JDP-AND-PMW-IN-LAB_slimInterdisciplinary Research
  • nm-schematic-fatElectrokinetic Locomotion of Nanorods

    Mitchell originally proposed that an asymmetric ion flux across an organism’s membrane could generate electric fields that drive locomotion. Although this locomotion mechanism was later rejected for some species of bacteria, engineered Janus particles have been realized that can swim due to ion fluxes generated by asymmetric electrochemical reactions. We have developed governing equations, scaling analyses, and numerical simulations that describe the motion of bimetallic rod-shaped motors in hydrogen peroxide solutions due to reaction-induced charge auto-electrophoresis. Electrokinetic locomotion results from electroosmotic fluid slip around the nanomotor surface driven by electrical body forces which are generated from a coupling of a reaction-induced dipolar charge density distribution and the electric field it creates.

  • Radial Flow Microfluidic Fuel CellMembraneless Microfluidic Fuel Cell
  • jdp-and-colloids_slimColloidal Science
  • Carbon-Nanotube-Interaction2Nano-Bio Interface
  • sslm_slimNano-Bio Interface
  • nanopore-cropNanofluidics

    We have fabricated silicon nanoscale pores and examined their electrokinetic transport behaviors.13, 26 We have shown that nanoscale pores in series with microchannels can exhibit asymmetric concentration polarization that can be leveraged for DNA sequencing, biomolecule separation, and desalination, for example.  We have also functionalized the pore with antibodies in the goal of developing nanofluidic biosensors.  In the presence of the target antigen the electrical conductance of the pore is modified.

UW_PRG_2013_HomeThe Posner Research Group’s (PRG) focus is micro- and nano scale transport physics at the interface of chemistry, materials, & biology. Our research has applications spanning energy, medicine, and the environment. Specific research topics include microfluidics and nanofluidic devices, colloidal science and interactions at fluid and solid interfaces, synthetic nanomotors, environmental and health impact of engineered nanomaterials, electrokinetics, low Reynolds number fluid instabilities, and fuel cells.