INVESTIGADORES
ABRAHAM Gustavo Abel
congresos y reuniones científicas
Título:
Characterization of elastomeric electrospun polyurethane scaffolds
Autor/es:
P.C. CARACCIOLO; F. BUFFA; V. THOMAS; G.A. ABRAHAM
Lugar:
Gramado, Brasil
Reunión:
Congreso; VI Congresso Latino Americano de Órgãos Artificiais e Biomateriais, VI COLAOB; 2010
Institución organizadora:
Sociedad Latinoamericana de Biomateriales, Ingeniería de Tejidos y Organos Artificiales, SLABO
Resumen:
The
development of elastomeric biodegradable and biocompatible segmented
polyurethanes (SPU) for use in tissue engineering applications has been
a subject of considerable interest in recent years. In this work, two different poly(e-caprolactone)-based SPU were synthesized using 1,6-hexamethylene diisocyanate (HDI) and novel chain extenders containing urea groups or an aromatic aminoacid derivative. Non-porous films
were prepared by casting of SPU solutions in N,N-dimethylacetamide
onto siliconized Petri dishes. Micro/nanofibrous scaffolds were
obtained by electrospinning technique. Thermal properties, as
determined by differential scanning calorimetry, were influenced both
by the different chemical structure of the hard segments and the
processing conditions. Mechanical properties, as examined by uniaxial
stress-strain behavior, showed lower values of elastic moludus, and
ultimate strain and tensile stress for the scaffolds. Swelling
and in vitro hydrolytic behaviors were tested in phosphate-buffered
solution (PBS) at 37 ºC for specific periods of time, while accelerated
degradation was studied in PBS solution at 70 ºC. Film samples displayed low swelling (less than 2 wt %), the values being much higher for the scaffolds. The introduction of the aminoacid derivative
chain extender with hydrolyzable ester bonds contributed to a higher
degradation of this SPU. Fibrous scaffolds exhibited higher hydrolytic
stability than films at shorter times of assay, due to their more
crystalline structures and higher degrees of association by hydrogen
bonding, but also higher mass loss values in the accelerated medium, suggesting that degradation rate is not constant but depends on the degradation time and the type of sample.