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100
Fully hydrated sample
Dispersion
50 wt%
40 wt%
10
35 wt%
25 wt%
20 wt%
15 wt%
10 wt%
1
5 wt%
0 wt%
0
1
2
3
4
q [nm
-1
]
Figure 5.13
Comparison of scattering curve from the oil-free MLO-based dispersion
(
25, gray line) with those from the oil-free nondispersed MLO-DGMO bulk
samples at
α
=
0 ,
β
=
25 with varying water content at 25°C. The intensities were shifted by
a constant arbitrary factor for the sake of visibility. The thick black line denotes the
scattering curve of the fully hydrated bulk sample. [Reprinted from Yaghmur et al.
( 2006b ).]
β
=
the maximum solubilized amount of water increased from approxi-
mately 32 wt % (de Campo et al., 2004) to approximately 41 wt % water
(Yaghmur et al., 2006b) at 25°C when the
value was varied from 0
(MLO-water mixture) to 25 (MLO-DGMO-water system) (Fig. 5.13).
2 .
Functionalization of the Self-Assembled Nanostructure
. Our results show
that DGMO signifi cantly enlarged the water channels in the fully
hydrated bicontinuous cubic phase. For example, the mean lattice param-
eter,
a
, increased from 8.4 to 10.6 nm with an increasing
β
value from 0
to 25 (Yaghmur et al., 2006b). This modifi cation was attractive for a
number of purposes; in particular, for enhancing the solubilization of
active molecules in the internal nanostructures. The functionalization of
the V
2
phases has also been described in recent studies (Angelov et al.,
2007 ; Yaghmur et al., 2007 ).
3 .
Dispersed vs. Nondispersed Systems
. We found a disagreement between
the nanostructure present in the dispersed particles and that of the fully
hydrated nondispersed bulk systems at equivalent
β
values. A typical
example is shown in Figure 5.13: The addition of DGMO promoted the
formation of a fully hydrated Pn3m cubic phase in the bulk while the
internal structure of the dispersed particles was of the Im3m type. Thus,
the behavior differed from that of the MLO-based system described in
β
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