Bioactive poly(L-lactic acid)-chitosan hybrid scaffolds

Poly(L-lactic acid)/Chitosan (PLLA/CHT) hybrid scaffolds were prepared by depositing CHT onto the pore walls in order to form a micro-structured low dense foam inside previously prepared PLLA scaffolds. The morphology and pore architecture of the scaffolds were evaluated by scanning electronic microscopy (SEM) and micro-computational tomography (micro-CT). The microstructure of the CHT fraction depends on its concentration in the solution used to impregnate the PLLA scaffolds. The water-uptake capability of the CHT fraction permitted the production of calcium-phosphate precursors in the structure of the hybrid constructs, on dipping them into alternate phosphorous and calcium solutions. Bioactivity tests, using incubation protocols in a simulated body fluid with ion concentrations approximately equal to those of human blood plasma, allowed the observation of the apatite deposition within the hybrid scaffolds, especially the ones with a higher CHT content. This work shows that bioactive scaffolds, with potential to be used in bone tissue engineering, can be obtained by combining chitosan with PLLA porous structures, following a simple and fast pre-calcification protocol.