Izon qNano, User Manual, Page: 15 / 56

FORCES EXPLANATION NOTES
Convection
Pressure-dependent force There is always a static
pressure head due to
gravitational force on the
fluid. An additional pressure
or vacuum can be applied
with the variable pressure
module (VPM) Convective forces tend to
dominate particle velocity in
larger pore systems
Electrophoresis
Voltage-dependent force Electrophoretic mobility
relates to the movement
of charged nanoparticles
through an electrolyte
solution towards an
oppositely charged
electrode. It is proportional
to particle surface charge
(
ζ
-potential) and the
applied voltage
Electrophoretic forces can
dominate particle velocity
in small nanopore systems,
when the applied voltage is
increased
Electro-osmosis
Voltage-dependent force The second electrokinetic
force is electro-osmosis.
Electro-osmosis relates
to the fluid flow caused
by currents of solvated
ions (ions surrounded by
water molecules) moving
along the surface of the
nanopore. It is proportional
to the nanopore surface
charge (
ζ
-potential) and the
applied voltage
Electro-osmosis is stronger
in some nanopore systems
(non-zeta capable pores),
but weak in others (good
zeta capable pores)
Summary of dominant forces at play in a nanopore system
Forces influencing the speed at which nanoparticles travel through the
nanopore are:
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