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!