CONDENSATION OF FLUORESCENT NANOPARTICLES USING A DEP CHIP WITH A
DOT – ELECTRODE ARRAY
STUDENT’S NAME : TRAN HONG CHUONG
陳紅章
CONTENT
I. INTRODUCTION
II. DEP THEORY AND NUMERICAL SIMULATION
III. MATERIAL AND METHODS
IV. RESULT AND DISCUSSIONS
V. CONCLUSION
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INTRODUCTION
DEFINITION OF DEP ; MICROFLUIDIC CHIP ; FLUORESCENT
SOME METHODS HAVE BEEN IMPLEMENTED BEFORE THIS PAPER
PURPOSE OF THIS PAPER
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DEFINITION OF DEP (DIELECTROPHORESIS)
The ability of an uncharged material to move when subjected to an electric field
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DEFINITION OF MICROCHIPS
Microfluidics deals with the behavior, precise control and manipulation of fluids that are geometrically constrained to a small, typically sub-millimeter, scale
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DEFINITION OF FLUORESCENT
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence
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SOME METHODS HAVE BEEN IMPLEMENTED BEFORE THIS PAPER
MAGNETIC FORCE IS A COMMON DRIVING FORCE FOR THE RAPID COLLECTION OF MAGNETIC
• CAN NOT APPLY TO METAL BASED ; POLYMER – BASED OR OXIDED BASED NANO PARTICLES SUCH AS GOLD NANOPARTICLES , PLANTINUM NANO PARTICLES.
• IT IS TOO DIFFICULT TO MINITURIZE FOR INTERGRATION WITH THE MEMS PROCESS.
PDMS MICROFILTER
• USING THIS KIND OF PASSIVE DEVICE , IT IS DIFFICULT TO CONTROL THE QUANTITY AND DISTRIBUTION OF NANO PARTICLES
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PURPOSE OF THIS PAPER
DEP manipulations was considered low cost ; intrinsic electrical control ; and compability with microfluids .
This paper develops a micro fluidics chip for programmable condensation of fluorescent – labeled nano particles based on DEP to enhance the strength of fluorescent density in a dot electrode array.
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DEP THEORY AND NUMERICAL SIMULATION
DEP EQUATION AND EXPLAIN
STRUCTURE OF DEP CHIP
SIMULATION RESULT
EFFECT OF BROWNIAN FORCE ON PARTICLE
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DEP EQUATION AND EXPLAIN
For a time-averaged dielectrophoretic force acting on a spherical particle immersed in a medium and exposed to a spatially non-uniform electric field.
3 22. . . . .[ ( )].DEP m p e msF R R K E
mIs the electrical permittivity of the surrounding medium .
pR Is the radius of the particle
2 2 2 2ms x y zE E E E Gradient of the square of the applied
electric field magnitude
. ( ) 0 0e DEPR K F Particle moved particle possessing a high intensity electric field.
. ( ) 0 0e DEPR K F Particle moved particle possessing a low intensity electric field.
. ( ) 0 0e DEPR K F The suspend particles will not be affected by the DEP force 9
STRUCTURE OF DEP CHIP & SIMULATION RESULT
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EFFECT OF BROWNIAN FORCE ON PARTICLE
1/2(12 / )B P BF R K T
Is a Gaussan random vector
Is a dynamic vicosity of fluid
PR Is the boltzman’s contrast
T Is the temperature and T =dt is the time step
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EFFECT OF BROWNIAN FORCE ON PARTICLE
3 22. . . . .[ ( )].DEP m p e msF R R K E
1/2(12 / )B P BF R K T
1/2 3; ;B P DEP P DEP BF R F R F F
This meant that the DEP force constructed in our chip was able to sufficiently manipulate 20 nm particles and overcome the Brownian motion effects.
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MATERIAL AND METHOD
SAMPLE PREPARATION
EXPERIMENT METHOD
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SAMPLE PREPARATION
In order to quantify the condensation of the NPs using DEP
force, nanoparticles were labeled by fluorescent protein
and observed by fluorescent optical microscopy.
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SAMPLE PREPARATION
In this experiment, we use Low-cost commercial aluminium oxide nano particles (Al2O3-NPs)
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EXPERIMENT METHOD
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EXPERIMENT METHOD
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EXPERIMENTAL RESULT AND DISCUSSION
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EXPERIMENT RESULT AND DISCUSSION
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CONCLUSION
This paper has developed a
DEP chip with a dot-electrode
array for the condensation of
nano particles and the
enhancement of fluorescent
intensity under a
programmable control system.
The condensation of
fluorescent-NPs increased
with either applied voltage,
applied time or nano
particle concentration
Our DEP system successfully
demonstrated the
immobilization of nano
particles on target
electrodes using
programmable control
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MANY THANKS FOR YOUR ATTENTION!