2 research outputs found
High Amorphous Vinyl Alcohol-Silica Bionanocomposites: Tuning Interface Interactions with Ionic Liquids
Herein, we demonstrate
the effect of imidazolium ionic liquids
(IL) applied as additives in the <i>in situ</i> formation
of high amorphous vinyl alcohol (HAVOH)-silica bionanocomposites,
using a simple solâgel process approach. A complementary set
of alkyl-, ether-, and carboxy-functionalized IL was used, allowing
silica structure control and polymerâsilica interphase tuning.
Consequently, hybrids with diverse morphologies, as well as improved
thermo-mechanical and barrier properties, were obtained. This diversity
also highlighted the systemsâ dependency on the ILâs
molecular structure, where both the cation and anion influenced the
hybridsâ final properties. This could be evidenced as the polar
group functionalized-IL (ether- and carboxy-functionalized IL) allowed
the formation of multiple hydrogen bonds at the organicâinorganic
interphase, inducing a fine hybrid morphology with well-dispersed
silica nanodomains. This significantly increased the storage (âŒ50%)
and tensile moduli (âŒ20%), extensibility (up to 300%), and
glass transition temperature (>20 °C) and decreased the water
vapor permeability (âŒ50%), which are desirable characteristics
for potential food and medical packaging
Multitask Imidazolium Salt Additives for Innovative Poly(lâlactide) Biomaterials: Morphology Control, Candida spp. Biofilm Inhibition, Human Mesenchymal Stem Cell Biocompatibility, and Skin Tolerance
Candida species have great ability to colonize and form biofilms on medical
devices, causing infections in human hosts. In this study, polyÂ(l-lactide) films with different imidazolium salt (1-<i>n</i>-hexadecyl-3-methylimidazolium chloride (<b>C</b><sub><b>16</b></sub><b>MImCl</b>) and 1-<i>n</i>-hexadecyl-3-methylimidazolium methanesulfonate (<b>C</b><sub><b>16</b></sub><b>MImMeS</b>)) contents were prepared,
using the solvent casting process. PolyÂ(l-lactide)-imidazolium
salt films were obtained with different surface morphologies (spherical
and directional), and the presence of the imidazolium salt in the
surface was confirmed. These films with different concentrations of
the imidazolium salts <b>C</b><sub><b>16</b></sub><b>MImCl</b> and <b>C</b><sub><b>16</b></sub><b>MImMeS</b> presented antibiofilm activity against isolates of Candida tropicalis, Candida parapsilosis, and Candida albicans. The minor
antibiofilm concentration assay enabled one to determine that an increasing
imidazolium salt content promoted, in general, an increase in the
inhibition percentage of biofilm formation. Scanning electron microscopy
micrographs confirmed the effective prevention of biofilm formation
on the imidazolium salt containing biomaterials. Lower concentrations
of the imidazolium salts showed no cytotoxicity, and the polyÂ(l-lactide)-imidazolium salt films presented good cell adhesion
and proliferation percentages with human mesenchymal stem cells. Furthermore,
no acute microscopic lesions were identified in the histopathological
evaluation after contact between the films and pig ear skin. In combination
with the good morphological, physicochemical, and mechanical properties,
these polyÂ(l-lactide)-based materials with imidazolium salt
additives can be considered as promising biomaterials for use in the
manufacturing of medical devices