Biomedical Engineering Reference
In-Depth Information
(a)
(d)
Control layer
Actuation chamber
Actuation chamber
Valve barrier
Network layer
Inlet
channels
Barrier
Metal valve seat
Glass substrate
(b)
Outlet
channel
Control layer
Closed valve
Actuation
chamber
(e)
Membrane
following
actuation
Network layer
Glass substrate
Metal valve seat
(c)
Actuation chamber
Inlet
channels
200 µm
Opened valve
Outlet channel
FIGURE 3.42
PDMS.“curtain”.microvalves..(From.Daniel.Irimia.and.Mehmet.Toner,.“Cell.handling.
using.microstructured.membranes,”.
Lab Chip
.6,.345,.2006..Reproduced.with.permission.from.The.
Royal.Society.of.Chemistry.)
3.8.1.8 PDMS Microvalve: The “Plunger Design”
If you have peeked in a toilet tank while you pull on the lush lever, you will have noticed how,
in most designs, it pulls a valve which looks like a radially symmetric plunger that is sealed
against a circular oriice. Sang Hoon Lee and coworkers of the University of Korea seem to have
found inspiration in macro-world components of this type when they designed a microluidic
valve that works in a similar way (
Figure 3.43
)—except that the force that closes the valve is
Closed valve
Air chamber
a
c
Pneumatic port
Air
chamber
Center
hole
Pneumatic layer
Hole layer
Air
Bas-relief plate
Membrane layer
Fluid inlet
Center hole
(diam. 100 µm)
Fluid outlet
100 µm
Thick centered membrane
b
d
Thin membrane
Outlet
Open valve
Vacuum
Thick center
Inlet
FIGURE 3.43
PDMS.“plunger”.microvalve..(From.Ju.Yeoul.Baek,.Ji.Young.Park,.Jong.Il.Ju,.Tae.Soo.
Lee,.and.Sang.Hoon.Lee,.“A.pneumatically.controllable.lexible.and.polymeric.microluidic.valve.
fabricated.via.in.situ.development,”.
J. Micromech. Microeng.
.15,.1015,.2005..Reproduced.with.
permission.from.the.Institute.of.Physics..Figure.contributed.by.Sang.Hoon.Lee.)
