Case 12601/13061/14016

High-Throughput Nanofluidic Desalting System Using Concentration Polarization Effect


Thermoelectric heat pumpsNanofluidic desalting systems, ion-permselectivity, proteomics, fluidic chip


Desalting of water and uses in biological engineering, including sample concentrator, protein/ion preconcentration, high-throughput microfluidic immunoassay, etc.

  • Low throughput due to extreme small volume of microfluidic devices
  • Significant sample loss caused by chip-to-world interfacing
  • Concentration range as wide as seven or more orders of magnitude
  • Reliability limit of immunoassay due to interference from background molecules


This invention combines electrokinetics and nanofluidic technology, and provides methods that purify solutions efficiently. The basic device is a fluidic chip comprising a planar array of channels through which a liquid containing a species of interest can be made to pass with at least one rigid substrate connected. A high aspect ratio ion-selective membrane is embedded within the chip. To realize the strong electrokinetic response, the main microchannel connects to a perm-selective nanochannel of 40 nm depth. Only ion and charged particles are trapped in the concentration region and only water can pass through the concentration zone and flow to the right reservoir with high speed. The whole system can be upgraded using massive multiplexed methods to achieve even higher throughput and successive concentration. The device can also consists of a number of microchannels which have one inlet and multiple outlets, and each outlet is open to external environment or connected to other components to eliminate the conventional buffer channel and yield higher flexibility to the system. The device is controlled by purely external electric field configuration, and no additional mechanical system is needed.

  • Desalting inside a microchip minimizing the sample loss during chip-to-world interfacing
  • Superior flow rate than any current electroosmotic pumping mechanism
  • Possibility to achieve successive preconcentration

  • Professor Jongyoon Han(Department of Electrical Engineering and Computer Science, MIT)
  • Dr. Sung Jae Kim (Department of Electrical Engineering and Computer Science, MIT)
  • Dr. Ying-Chih Wang (Sandia National Laboratories, CA)
  • Sung Hee Ko (Pohang University of Science and Technology, Korea)

Intellectual Property:

US Patent and PCT filed on March 23, 2009



Last revised:November 8, 2010

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