278
loaded in the gel phase, and pH, enable the proposal of a molecular picture of loading. The loading of Caf in NS hydrogels tends to
favor access of the water solvent to the more hydrophobic portions
of the polymer matrix, which is in turn reflected in a marked
increase in the solvation of the whole system. The results of this
work appear to be of interest with respect to the design of new
possible strategies for controlling the diffusion/release of bioactive
molecules inside hydrogel networks to give new molecular insights
into complex phenomena affecting the hydrogel phase [117].
Organic/inorganic hybrid filters based on dendritic and cyclodextrin nanosponges which are completely insoluble in water have
the property of encapsulating organic pollutants from water [118].
Ceramic porous filters impregnated with these compounds were
tested for the effective purification of water, by continuous filtration experiments, employing a variety of water pollutants. It has
been established that polycyclic aromatic hydrocarbons (PAHs)
can be removed very efficiently (more than 95%), and final concentrations of several ppb (μg/L) are easily obtained. Representatives
of the pollutant group of trihalogen methanes (THMs), monoaromatic hydrocarbons (BTX), and pesticides (simazine) can also be
removed (>80%), although the filters are saturated considerably
faster in these cases. For the efficient absorption of the more polar
substances employing hybrid organic/inorganic filter modules,
increased impregnation percentage and adequate contact time
between the alkylated compounds and the polluted water are
required. The latter can be achieved by low flow rates, increased
length of the ceramic membranes, or, alternatively, recirculation of
the polluted water. By careful selection of the suitable materials
and processing parameters the application of these composite filters may be extended and adopted for specific cases of water purification [119].
New water-soluble hyper-branched β-CD polymer was synthetized and characterized. The synthetic route proposed seems to be
quite independent from the reaction time. The new polymer exhibits an exceptionally high solubility in water, DMF, and DMSO
while it is insoluble in low polar solvents and at very low pH. The
polymer shows good complexing properties toward organic molecules. In addition, it strongly interacts with several metal cations
able to precipitate in the presence of Cu
2+
, Fe
3+
, Ba
2+
, Cd
2+
, Pb
2+
,
and Sn
2+
, by forming metal–organic complexes showing some
selectivity toward certain metal cations and indirect evidence of
polyelectrolyte behavior [120].
3 Conclusion
Cyclodextrin-based nanosponges constitute an atypical class of
biocompatible delivery system that allows a smooth transformation
Maria Tannous et al.
loaded in the gel phase, and pH, enable the proposal of a molecular picture of loading. The loading of Caf in NS hydrogels tends to
favor access of the water solvent to the more hydrophobic portions
of the polymer matrix, which is in turn reflected in a marked
increase in the solvation of the whole system. The results of this
work appear to be of interest with respect to the design of new
possible strategies for controlling the diffusion/release of bioactive
molecules inside hydrogel networks to give new molecular insights
into complex phenomena affecting the hydrogel phase [117].
Organic/inorganic hybrid filters based on dendritic and cyclodextrin nanosponges which are completely insoluble in water have
the property of encapsulating organic pollutants from water [118].
Ceramic porous filters impregnated with these compounds were
tested for the effective purification of water, by continuous filtration experiments, employing a variety of water pollutants. It has
been established that polycyclic aromatic hydrocarbons (PAHs)
can be removed very efficiently (more than 95%), and final concentrations of several ppb (μg/L) are easily obtained. Representatives
of the pollutant group of trihalogen methanes (THMs), monoaromatic hydrocarbons (BTX), and pesticides (simazine) can also be
removed (>80%), although the filters are saturated considerably
faster in these cases. For the efficient absorption of the more polar
substances employing hybrid organic/inorganic filter modules,
increased impregnation percentage and adequate contact time
between the alkylated compounds and the polluted water are
required. The latter can be achieved by low flow rates, increased
length of the ceramic membranes, or, alternatively, recirculation of
the polluted water. By careful selection of the suitable materials
and processing parameters the application of these composite filters may be extended and adopted for specific cases of water purification [119].
New water-soluble hyper-branched β-CD polymer was synthetized and characterized. The synthetic route proposed seems to be
quite independent from the reaction time. The new polymer exhibits an exceptionally high solubility in water, DMF, and DMSO
while it is insoluble in low polar solvents and at very low pH. The
polymer shows good complexing properties toward organic molecules. In addition, it strongly interacts with several metal cations
able to precipitate in the presence of Cu
2+
, Fe
3+
, Ba
2+
, Cd
2+
, Pb
2+
,
and Sn
2+
, by forming metal–organic complexes showing some
selectivity toward certain metal cations and indirect evidence of
polyelectrolyte behavior [120].
3 Conclusion
Cyclodextrin-based nanosponges constitute an atypical class of
biocompatible delivery system that allows a smooth transformation
Maria Tannous et al.