d	electrode length (μm or m)
E	electric field
H	height (m or μm)
g	electrode gap (μm or m)
ga	acceleration due to gravity (m/s2)
F	force vector (N)
Ks	surface conductance (S)
l	length of repeating unit (μm or m)
N	operating frequency (kHz)
m	mass (kg)
n	number of electrodes (-)
P	pressure (Pa)
Q	flow rate (m3/s or μL/h)
Re[fCM]	Clausius–Mossotti factor (-)
r	radius (m or μm)
SE	separation efficiency
SP	separation purity
t	time (s)
U	velocity vector (m/s)
u	velocity along x-direction (m/s)
V	voltage (V)
W	width (m or μm)
w	electrode width (μm or m)
X	displacement vector (m or μm)
x	displacement in the x-direction (m)
y	displacement in the y-direction (m)
z	displacement in the z-direction (m)
$\overline{x}$	co-ordinate in the x-direction
$\overline{y}$	co-ordinate in the y-direction
$\overline{z}$	co-ordinate in the z-direction
Greek alphabet
ε	permittivity (-)
εo	permittivity of free space (F/m)
σ	conductivity (S/m)
μ	viscosity (Pa∙s)
ρ	density (kg/m3)
ω	operating frequency (rad/s)
Subscripts
2	2-μm particle
2.25	2.25-μm particle
bp	big microparticle
bulk	bulk electrical conductivity
ch	microchannel
cr	cross-over
DEP	dielectrophoresis
ext	external
e	entity
ext	external
f	focusing section
m	medium
o	outlet
RMS	root mean square
s	separation section
sp	small microparticle