Designing Chitosan-CMC scaffolds for biomedical application

M. SOLEDAD BELLUZO; LARA F. MEDINA; M. SUSANA CORTIZO

Rosario

Congreso; 8vo Congreso Latinoamericano de Órganos Artificiales, Biomateriales e Ingeniería de Tejidos- 8vo COLAOB; 2014

Bone regeneration research is a growing area in tissue engineering and the combination of biodegradable polymers with osteogenic agents is one of the most employed techniques. To produce a functional in vitro tissue it is necessary to design a scaffold with specific mechanical and structural properties that promote cell adhesion, proliferation and differentiation. These properties are related to the selected biomaterial and the scaffold synthesis (1-3). The goal of this work was to obtain two biodegradable scaffolds. The first one was a polyelectrolyte complex obtained from the electrostatic combination of two natural polyelectrolytes, one cationic (chitosan ?CHI-) and other anionic (carboxymethylcellulose ?CMC-). The second one was obtained with same polyelectrolytes but they were combined with ultrasound. The scaffolds were prepared from 1% w/v CHI solutions in 1% w/v acetic acid and 1% w/v CMC. In all cases, the samples were obtained by dropping CMC into CHI under constant stirring and later, part of the solution was treated with ultrasound. Finally, the scaffolds were freeze-drying until constant weight was achieved. The structure of the polymer was characterized by Fluorescence Microscopy (FM) and a Scanning Electron Microscopy (SEM). The effect of the ultrasound treatment was analyzed by FTIR-ATR. Finally, compression and swelling test were performed. The FM and SEM results showed a three-dimensional porous structure for the CHI-CMC scaffolds. The mean pore size was suitable for cell proliferation. In addition, the morphology of the polymer treated with ultrasound was more compact, probably due to strong interactions between CHI and CMC. The FTIR-ATR results demonstrated that CHI and CMC were covalently bonded due to the presence of bands related to amide groups. Finally, the compression test and swelling studies showed significant differences between the two scaffolds corresponding to the CHI-CMC interaction type.