INVESTIGADORES
ABRAHAM Gustavo Abel
congresos y reuniones científicas
Título:
Nanofibrous scaffolds containing conductive nanoparticles
Autor/es:
F. MONTINI BALLARÍN; F. BUFFA; G.A. ABRAHAM
Lugar:
Rosario, Santa Fé
Reunión:
Taller; 1º Taller de Órganos Artificiales, Biomateriales e Ingeniería de Tejidos (BIOOMAT); 2009
Institución organizadora:
UNR, CAIC y SLABO
Resumen:
Nanofibrous polymeric scaffolds have biomimetic features and can create an extracellular matrix architecture in a nanoscale way. Recognizing
the importance of electrical and mechanical properties for several
tissue reconstruction, conductive nanofibrous scaffolds are interesting
candidates for tissue engineering and biotechnological applications. In
this work we report the development of polyurethane-based nanocomposite
scaffolds with conductive properties obtained by electrospinning.
Electrospun polyurethane scaffolds containing single-walled carbon
nanotubes (SWCNT) or polyaniline (PANI) 0.5, 1, 1.5 and 2% wt, were
prepared. Medical-grade aliphatic polyurethane (Tecoflex 60D) was
dissolved in dimethylformamide. The polyurethane solutions were mixed
with suspended nanoparticle in tetrahydrofuran and the mixture sonicated
until complete homogenization. The content and dispersion of
nanoparticles played an important role in the electrospinnability of the
solutions. The processing conditions were optimized in order to obtain
uniform bead-free nanofibrous membranes. The residual solvent was
completely removed under vacuum and the morphology of the prepared
membranes was examined by SEM. An effect in the microstructure was
found,: the mean diameter of the nanofibers decreased with the increase
in the nanoparticle content. For 1.5% wt SWCNT a mean diameter of 464 nm
was measured, while in the case of the same concentration of PANI a 430
nm in diameter was observed. In all cases, a unimodal diameter
distribution was obtained. Conductivity measurements were performed by
four-probe method, and by impedance mesuarements using a LCR meter. The scaffolds showed an increase in the conductivity, both a.c and d.c.
conductivity, with an increase in the nanoparticles concentration.
However, with both types of composites the nanoparticle content
exhibited an upper limit, above which the conductivity decreased. The
scaffolds containing polyaniline nanotubes presented significant higher
conductivity values. Further studies on the nanoparticle
dispersion-aggregation in the nanofiber and nanofiber roughness are
under progress.