Analysis of Dielectrophoretic Force by Using COMSOL
Department of Biomedical Engineering,Yonsei Universityy
Taewoo Lee
COMSOL CONFERENCE SEOUL 2013
Prof. Han-Sung KimCompuater Aided Biomedical Engineering Lab.p g ghttp://cabe.yonsei.ac.kr
Prof. Sang Woo LeeNano Bio System Research LabNano Bio System Research Lab.http://nbsrl.yonsei.ac.kr
Dielectrophoresis is a phenomenon in which a force is exerted on a dielectric particle when it is subjected to a non-uniform electric fielddielectric particle when it is subjected to a non-uniform electric field.
OutputSide view
p
Ground
Cover glass Silicon rubber
Glass substrate Electrode Medium (Cells or Beads)
Cover glass Silicon rubber
Top view
Cells or BeadsCells or Beads
Side view
Top view
SiO2 insulator Opening window
Unit model for simulation
45μmElectrode without SiO2
(Opening window)
13μm
zx
y
Gap betweenthe electrodes
0μm
5μm
yxElectrode with SiO2-8μm
0μm-5μm 10μm
Governing equations
• Dielectrophoretic (DEP) forcep
• Elecrohydrodynamic force
- Electrothermal force
• Gravitational & buoyant forcey
COMSOL Multiphysics 3.5a
MEMS
ModuleElectrostatics Electrostatics
COMSOL
MultiphysicsHeat Transfer
Convection and
Conduction
MEMSMEMS
ModuleMicrofluidics
Incompressible
Navier-Stokes
Results
• Slice: Temperature
• Arrow: Total heat flux
• Streamline: Velocity field
Result – Positive DEP
l b h h l d• Equilibrium height: Particle radius
N1.47e-19
N2.87e-9
1e-19
1e-20
1e-10
1e-11
1e-21
1e-22
1e-12
1e-13
1.78e-23
z
5.92e-15
Equilibrium heighty
DEP force EHD force
Equilibrium height
Result – Positive DEP
N
3.6e-10
N5.37e-10
y
2.7e-10
1.8e-10
Trapped position x
y
0.9e-10
7.26e-12
Result – Negative DEP
l b h h f• Equilibrium height: Net force = 0
N1.34e-9
N6.17e-14
1e-9
1e-10
1e-14
1e-15
1e-11
1e-12
1e-16
1e-17
z
2.11e-15 8.11e-18
y
DEP force EHD force
Result – Negative DEP
l b h h f• Equilibrium height: Net force = 0
DE
xy
Cxy
Result – Negative DEP
9.6e-15
N1.26e-14
7.2e-15
4.8e-15
2 4e-15
xy
2.4e-15
4.67e-16
Dotted line ATrapped position
Simulation vs. Experiment
Positive DEP
Negative DEPNegative DEP
5μm polystyrene beads
CM factor (Cells vs. Beads)
CM factor
Cells
Beads
CM factor
Frequency
DEP traps for single cell (B16F10)
Positive DEP force (3Vpp, 100kHz)Negative DEP force (3Vpp, 1kHz)
Positive DEP Trap in various window shapes
Rh b S HRhombus Square Hexagon
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