1276
S. Palma et al. / Il Farmaco 58 (2003) 1271ꢀ1276
/
Finally, taking into account the potential utilization
carriers, especially for rather hydrophobic and easily
degradable products.
of these semisolids systems as drug carriers, the incor-
poration of an antipsoriatic drug (anthralin) [15] was
evaluated as well as its influence in the rheology of the
coagels.
The amount of anthralin loaded into ASCn coagels
increased linearly with n. However, the load capacity is
Acknowledgements
Partial financial support from Consejo Nacional de
Investigaciones Cient´ıficas y Te´cnicas (CONICET) and
the Consorzio Interuniversitario per lo Sviluppo dei
Sistemi a Grande Interfase (CSGI), Ministero dell’Is-
truzione, dell’Universita` e della Ricerca (MURST), is
greatly acknowledged.
higher for nꢀ12 [16]. This behavior could be attributed
/
to the gel configuration of ASC14 and ASC16 disper-
sions at temperature above TMC [8], where lamellar
configuration would permit higher drug solubilization
comparatively to micellar dispersions of ASCn with
lower molecular weight.
Regarding the rheological properties of anthralin
loaded coagels, the drug incorporation have no effect
on the semisolid structure. In Fig. 4 the rheogram of
anthralin loaded ASC14 coagel is depicted. As it occurs
with ASC14 unloaded coagel (Fig. 2e), a spur value is
observed and it is indicative of a high structured liquid
crystal. This fact permit to infer that the solubilization
of drug in the lipophilic portion of the coagel do not
affect the interaction between the solvent (water) and
the hydrophilic portion of ASCn.
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