Decellularized Bovine Articular Cartilage Matrix Reinforced by Carboxylated-SWCNT for Tissue Engineering Application

Nanotubes with their unique properties have diversified mechanical and biological applications. Due to similarity of dimensions with extracellular matrix (ECM) elements, these materials are used in designing scaffolds. In this research, Carboxylated Single-Wall Carbon Nanotubes in optimization of decellularized scaffold of bovine articular cartilage was used. At first, the articular cartilage was decellularized. Then the scaffolds were analyzed in: (i) decellularized scaffolds, and (ii) scaffolds plunged into homogenous suspension of nanotubes in distilled water, were smeared with Carboxylated-SWCNT. The tissue rings derived from the rabbit's ear were assembled with reinforced scaffolds and they were placed in a culture media for 15 days. The scaffolds in two groups and the assembled scaffolds underwent histologic and electron microscopy. Scanning electron microscopy showed that the structure of ECM of articular cartilage has been maintained well after decellularization. Fourier transform infrared analysis showed that the contents of ECM have not been changed under treatment process. Atomic force microscopy analysis showed the difference in surface topography and roughness of group (ii) scaffolds in comparison with group (i). Transmission electron microscopy studies showed the Carboxylated-SWCNT bond with the surface of decellularized scaffold and no penetration of these compounds into the scaffold. The porosity percentage with median rate of 91.04 in group (i) scaffolds did not have significant difference with group (ii) scaffolds. The electron microscopy observations confirmed migration and penetration of the blastema cells into the group (ii) assembled scaffolds. This research presents a technique for provision of nanocomposite scaffolds for cartilage engineering applications.