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structure (LC phase), and temperature recycling (up and down scans) (Guillot
et al., 2009b; Tomsic et al., 2008, 2009). Various characterization tools, including
SAXS, DLS, differential scanning calorimetry (DSC), and oscillatory rheolo-
gical experiments, were utilized to demonstrate the incorporation of ISA-
somes into the hydrogels.
A mere 2% gelling agent is suffi cient to form quite a strong network
(storage modulus,
G
10
4
- 10
6
Pa). The ISAsomes stay practically intact, having
the same size before and after gelation and dilution (Fig. 6.12a), as confi rmed
by DLS (Tomsic et al., 2009). However, the phase behavior of ISAsomes
was, in general, only slightly affected by the gel interactions, although it
′∼
0.3
d
= 85% in water
(a)
e
MC
= 2%, before gelation
e
MC
= 2%, after degelation
0.2
0.1
0.0
0
100
200
300
400
R
H
[nm]
(b)
(c)
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
1.18 1.20 1.22 1.24 1.26 1.28 1.30 1.32 1.34 1.36
a) EME 25°C
a) EME 60°C
c) Loaded k-carrageenan gel 25°C
d) Loaded k-carrageenan gel 60°C
T=25°C
1
1
b)
c)
c)
c)
a)
b)
d)
0.1
a) Carrageenan/water
b) Hexosomes
b) Hexosomes/Carrageenan/water-After preparation
Hexosomes/Carrageenan/water-After 1 day
b)
δ
= 54.3
a)
0.1
0.01
0
1
2
3
0
1
2
3
q (nm
−1
)
q (nm
−1
)
Figure 6.12
Embedding ISAsomes in hydrogels: (a) Thermoreversibility test of the
integrity of hexosomes (DU/TC system,
85) as particles during gelation-degelation
of 2% MC by DLS. The data were obtained via inverse Laplace transformation for the
individual steps of the temperature cycle 25 ° C (sol) - 70 ° C (gel) - 25 ° C (sol) on 4000
δ
=
×
diluted samples. (b) SAXS data from hexosomes (DU/LM system,
83.3). Inset: the
scattering curve of the KC-water system was subtracted from the hexosomes-KC-
water scattering curve. There was no change observed even after one day in the
hexosome-KC system. The hexagonal phase remained intact; only the peak position
was shifted. (c) SAXS data from EME (DU/LM system,
δ
=
54.3) at 25 and 60 ° C. The
EME converts into Fd3m micellar phase due to interference from KC. [Figures (a) and
(b) were taken from Tomsic et al. (2009) and (c) from Guillot et al. (2009b).]
δ
=
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