The aim of this study was to evaluate the possibility of preparing starch-based porous matrixes using
supercritical fluid technology. Supercritical immersion precipitation technique was used to prepare scaffolds
of a polymeric blend of starch and poly(l-lactic acid) for tissue engineering purposes.Immersion
precipitation experiments were carried out at different operational conditions and highly porous and
interconnected scaffolds were obtained. Two organic solvents, dichloromethane and chloroform were
tested, and from the results obtained chloroform was the more favourable for the process. The effect of
polymer solution concentration (5 up to 20 wt%), temperature (35 up to 55 ◦C) and pressure (100 up to
200 bar) in the SPLA (50:50 wt%) membrane morphology, porosity and interconnectivity was evaluated.
All the conditions tested were in the region of total miscibility between the organic solvent and carbon
dioxide. Additionally, a blend with a different starch-poly(l-lactic acid) ratio (30:70 wt%) was tested.
Bicontinuous structures were formed indicating that the L–L demixing process that governs the phase
inversion is the spinodal decomposition.Ana Rita C. Duarte is grateful for financial support from Fundacao para a Ciencia a Tecnologia through the grant SFRH/BPD/34994/2007
