43 research outputs found
ÁREA DE PRESIDENCIA [Material gráfico]
Forma parte del reportaje fotográfico sobre la inauguración en los años 40 del nuevo edificio institucional del Cabildo de Gran CanariaCopia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201
The double porogen approach as a new technique for the fabrication of interconnected poly(L-lactic acid) and starch based biodegradable scaffolds
One of the most widely used fabrication methods
of three dimensional porous scaffolds involves compression
moulding of a polymer salt mixture, followed by salt leaching.
However, the scaffolds prepared by this technique have
typically limited interconnectivity. In this study, besides salt
particles, an additional polymeric porogen, poly(ethylene oxide),
PEO, was added to poly(L-lactic acid), PLLA, to enhance
the interconnectivity of the scaffolds. Compression
moulded specimens were quenched and put intowater, where
PEO crystallized and phase separated. Following the leaching
of PEO fraction, the permeability and interconnectivity
among the macropores formed by salt leaching could be
observed. The porosities obtained in the prepared scaffolds
were between 76 to 86%. Moreover, the highest porosity
of 86% was obtained with minimum fraction of total porogen.
The water absorption of the porous scaffolds prepared
with PEO could vary between 280 to 450% while water
uptake of pure PLLA scaffolds was about 93%. The increase
of interconnectivity induced by compounding PLLA
with PEO could also be obtained in porous PLLA/starch
blends and PLLA/hydroxyapatite composites demonstrating
the versatility and wide applicability of this preparation
protocol. The simplicity of this organic solvent free
preparation procedure of three-dimensional porous scaffolds with high interconnectivity and high surface area to volume
ratio holds a promise for several tissue engineering
applications