@article {15337, title = {Melt-based Compression Moulded Scaffolds from Chitosan-Polyester Blends and Composites: Morphology and Mechanical Properties}, journal = {Journal of Biomedical Materials Research: Part A.}, year = {2008}, month = {2008-01-17 00:00:00}, abstract = {

Blends of chitosan and synthetic aliphatic poly- esters (polybutylene succinate, polybutylene succinate adi- pate, polycaprolactone, and polybutylene terepthalate adi- pate) were compounded with and without hydroxyapatite, a bioactive mineral filler known to enhance osteoconduc- tion. The blends and composites were compression molded with two different granulometric salt sizes (63{\textendash}125 lm and 250{\textendash}500 lm) having different levels of salt content (60, 70, and 80\%) by weight. By leaching the salt particles, it was possible to produce porous scaffolds with distinct morphol- ogies. The relationship between scaffold morphology and mechanical properties was evaluated using scanning elec- tron microscopy, microcomputed tomography, compression testing, differential scanning calorimetry, small-angle X-ray scattering (SAXS), and wide-angle X-ray scattering. The pro- duced scaffolds are characterized by having different mor- phologies depending on the average particle size and the amount of NaCl used. Specimens with higher porosity level have a less organized pore structure but increased intercon-

nectivity of the pores. The stress{\textendash}strain curve under com- pression displayed a linear elasticity followed by a plateau whose characteristics depend on the scaffold polymer com- position. A decrease in the salt particle size used to create the porosity caused in general a decrease in the mechanical properties of the foams. Composites with hydroxyapatite had a sharp reduction in yield stress, modulus, and strain at break. The melting temperature decreased with increased chitosan content. SAXS results indicate no preferential crys- talline orientation in the scaffolds. Cytotoxicity evaluation were carried out using standard tests (accordingly to ISO/ EN 10993 part 5 guidelines), namely MTS test with a 24-h extraction period, revealing that L929 cells had comparable metabolic activities to that obtained for the negative control.

}, keywords = {biodegradable blends, Chitosan, poly-esters, scaffolds, Tissue engineering}, doi = {10.1002/jbm.a.32221}, author = {Correlo, V. M. and Boesel, L. F. and Pinho, E. D. and Costa-Pinto, A. R. and Alves da Silva, ML and Bhattacharya, M. and Mano, J. F. and Neves, N. M. and Reis, R. L.} }