A Micro-flow Cytometer Based on Dielectrophoretic Particle Focusing

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A Micro-flow Cytometer Based on Dielectrophoretic
Particle Focusing
Choongho Yu, Li ShiUniversity of Texas at
Austin Jody Vykouka, Peter GascoyneUT MD
Anderson Cancer CenterSupportUT BME Program
/Whitake Foundation
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Conventional Flow Cytometry
Hydrodynamic Focusing
Picture Courtesy Purdue University Cytometry
Laboratories

1. Focus cells in suspension by sheath fluid
2. Illuminate cells in the focused suspension stream
   
3. Analyze cells by detecting scattered and
   fluorescence signals

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Motivation for a Micro-cytometer
Conventional Micro (Goals)
User Interface Complex Operated by skilled personnel Easier to operate
Size etc. Large, heavy ? A reservoir is required for the sheath flow medium, and need to be kept free of dust and bacteria Small, portable ? Large components unnecessary ? Eliminate the use of gallons of sheath liquid
Price Expensive Inexpensive

• Collaboration P. Gascoyne, UT MD Anderson Cancer
  Center

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Dielectrophoretic (DEP) Particle Focusing
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A Micro-Flow Cytometer based on DEP Focusing
Circular electrode
Top glass wafer
Circular channel
Bottom Si wafer

• Electrodes focus cells to the center of the
  channel by negative DEP force
• Optical sensors can be fabricated on the bottom
  Si wafer for cell diagnostics

Electrode
Circular channel
PhD Student Choongho Yu
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Proof of Principle