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MANIPULATION OF WHOLE BLOOD USING TRAVELING WAVE DIELECTROPHORESIS
Y.J. Lo, A.M. Wo, and U. Lei
Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
(MEMS2005 P.686~689)
Reporter: Chung-Kuang Chin( 秦重光 )
Date:10/24/2007
Motivation
Beautiful Life, Money -> Health Care -> Bio-Medical Science + MEMS -> Bio-MEMS ( “Lab on a Chip” ,” Micro-total analysis system” ) -> cell manipulation (μm) -> DEP force (working on whole blood is rare) -> This paper !!!! (MANIPULATION OF WHOLE BLOOD USING TRAVELING WAVE DIEL
ECTROPHORESIS ) -> But after Reading ,… @#&%*!
Ref: http://www.imm-mainz.de/upload/bilder/d137027ad17056118590d74d1c2b8b30.orig.jpg
Introduction
DEP - conventional DEP (cDEP) 、 rotation DEP (rotDEP) 、 traveling-wave DEP (twDEP)
10MHz
Theory - DEP/twDEP DEP force - factor : non-uniform electric field 、 electrical properties of particles & m
edium
Ref: http://www.ibmm.informatics.bangor.ac.uk
Theory Formula
DEP force
( , Clausius–Mossotti factor
ε : permittivity , , σ : conductivity , ω : angular frequency , r : particle radius
: rms value of the electric field strength ,
, (i=x,y,z) : magnitude , phase ) Real part -> (Conventional) DEP , Imaginary part -> twDEP
3 * 2 * 2 2 22 Re Imm rms x x y y z zF t r K E K E E E
**
**
*
2 mp
mpK
ppp j*
mmm j*
rmsE
iE i
Particle Manipulation using DEP & twDEP
Figure When a particle is suspended in an alternating electric field which contains either a magnitude or phase gradient, a force is induced on the particle which acts either in the direction of the gradient or opposes it, according to whether or not the particle is more or less Polari able than the medium in which it is suspended.
Here, a particle experiences force due to (a) a non-uniform electric field (magnitude gradient); (b) a traveling electric field (phase gradient
Fabrication
Electrode (Cr) Micro-channel (PDMS) Bonding (O2 plasma)
Ref: http://www.ndl.org.tw/old/ndlcomm/P12_1/3.pdf
Experiment Results (1)
motion of whole blood cells being pumped by twDEP with phasing between electrodes
Experiment Results (2)
Effect of electrode gap and voltage on average cell velocity
Fdrag α Velocity FDEP α (Voltage)*2