266 Color Inserts
Ϭ͘Ϭϭ
Ϭ͘ϭ
ϭ
ϭϬ ϭϱ ϮϬ Ϯϱ ϯϬ
Ϭ͘Ϯϱϯ
Ϭ͘Ϯϳϱ
Ϭ͘Ϯϴ
Ϭ͘ϯ
ϯ
WK
ϰ
ŽŶĐĞŶƚƌĂƚŝŽŶ΀ŵŽůͬ
sŝƐĐŽƐŝƚLJ;WĂ ƐͿ
ŵƉĞƌĂƚƵƌĞ;ΣͿ
Figure 6.3 Viscosity as a function of temperature for high concentrations of sodium
phosphate in a 15 wt% Pluronic F127 solution in water from cone and plate viscometry
at controlled shear stress (0.6 Pa s).
110
Figure 6.5 A schematic illustration of the principle of an active valve using a thermally
responsive fluid in a microfluidic network. (a) Fluid from one channel is d iverted into two
channels at a channel bifurcation; (b) activating an integrated heater leads to localized gel
formation in the corresponding microchannel, which subsequently blocks this channel to
flow.
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Color Inserts 267
Figure 6.7 A schematic cross-section of the microfluidic device shown in Fig. 6.6. The left-
hand side shows the cross-section across a heater in the channel, while the right-hand side
shows a cross-section further away from the channel, through an aluminum lead.
D
E
Figure 6.9 The flow field at the channel bifurcation shown in Fig. 6.6. The velocities
were evaluated from images of the seed particles as in Fig. 6.8 using PIV; (a) before valve
actuation, (b) 33 ms later; blue: below 40 μm/s, green: 40–80 μm/s, yellow: 80–120 μm/s,
orange: 120–160 μm/s.
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268 Color Inserts
Figure 6.10 Experimental setup for the demonstration of passive flow control using ther-
mally responsive Pluronic solutions at constant flow rate in microchannels.
Figure 6.14 Top view of a microfluidic device. Pluronic solution and saline solution are
introduced in a 10 μm high microchannel at T
a
=24
C. Gel formation occurs in the center
of the channel. The Pluronic stream is seeded with fluorescent particles.
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Color Inserts 269
Figure 6.16 Thickness of the gel wall along the channel for different experimental condi-
tions.
Figure 7.5 BioMEMS multi-array prototype implanted subcutaneously in a rodent model.
The local environment had encapsulated the device in an attempt to isolate it from the body
(28 days post-implantation).
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270 Color Inserts
Figure 7.8 BioMEMS micro-array prototype. The inner-reservoir surface area is larger than
it appears from a top view (A). The activation of the entire multi-array reservoir system
leads to dissolution of the reservoir sealing membrane, release of the drug, and the onset of
a “new inflammatory response initiated by the exposed surface of the inner reservoir (B).
Figure 8.1 Amount of protein adsorption on a given oligoether SAM on gold normalized
to the amount of protein adsorbed on a monolayer of hexa-decanethiol on gold (100%)
versus advancing aqueous contact angle of the SAM. Symbols: red
,EG
2
OH; orange,
EG
3
OH; green+,EG
6
OH; blue,TRI
3
OH; blue ,EG
1
OMe; green,EG
2
OMe; light blue ,
EG
3
OMe; red ×,EG
6
OMe; blue ,TRI
3
OMe; red ×,PRO
2
OMe; blue,PRO
3
OMe; orange
+,PRO
4
OMe; purpl,EG
3
OEt; green,EG
6
OEt; blue,EG
3
OPr; green,EG
6
OPr; blue ,
EG
3
OBu. Images adapted from Ref. 54.
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