Assessment of the Suitability of Chitosan/PolyButylene Succinate Scaffolds Seeded with Mouse Mesenchymal Progenitor Cells for a Cartilage Tissue Engineering Approach

In this work, scaffolds derived from a new biomaterial originated from the combination of a natural material and a synthetic material were tested for assessing their suitability for cartilage tissue engi-neering applications. In order to obtain a better outcome result in terms of scaffolds ’ overall properties, different blends of natural and synthetic materials were created. Chitosan and polybutylene succinate (C-PBS) 50/50 (wt%) were melt blended using a twin-screw extruder and processed into 555 mm scaf-folds by compression moulding with salt leaching. Micro-computed tomography analysis calculated an average of 66.29 % porosity and 92.78 % interconnectivity degree for the presented scaffolds. The salt particles used ranged in size between 63 and 125 lm, retrieving an average pore size of 251.28lm. Regarding the mechanical properties, the compressive modulus was of 1.73 ± 0.4 MPa (Esec 1%). Cyto-toxicity evaluation revealed that the leachables released by the developed porous structures were not harmful to the cells and hence were noncytotoxic. Direct contact assays were carried out using a mouse bone marrow–derived mesenchymal progenitor cell line (BMC9). Cells were seeded at a density of 5105 cells/scaffold and allowed to grow for periods up to 3 weeks under chondrogenic differentiating condi-tions. Scanning electron microscopy analysis revealed that the cells were able to proliferate and coloniz