Effects of formaldehyde solution and nanoparticles on mechanical properties and biodegradation of gelatin/nano β-TCP scaffolds

In this study, gelatin/beta tricalcium phosphate (beta-TCP) nanocomposite scaffolds were prepared by solvent casting method. The cross-linking method was carried out by adding formaldehyde to gelatin. The microparticles of sodium chloride were used as porogen agent. Characterization of nano beta-TCP was performed using XRD, FTIR, and SEM. Results showed that the size of the particles is about 100 nm with spherical morphology. In addition, the scaffold characterization was carried out using FTIR and SEM techniques. Observations showed a porous texture with pore size between 100 and 400 mu m. The biodegradability and bioactivity evaluations of the scaffolds were done by immersing them in a simulated body fluid solution for different time periods. The biodegradability studies demonstrated a reduction in the degradation rate of gelatin/beta-TCP nanocomposite scaffolds due to the presence of beta-TCP nanoparticles. The obtained results of bioactivity tests confirmed the formation of apatite layer on the surface of the scaffolds. Furthermore, the effects of porosity, cross-linking agent, and beta-TCP nanoparticles on the bending and compressive properties of the composite scaffolds were examined. According to the mechanical examinations of the scaffolds, the best bending and compressive properties occurred in the presence of 10 and 20 wt% of beta-TCP nanoparticles, respectively. The appropriate mechanical properties and biodegradation rate for tissue engineering applications obtained at 1 g of the formaldehyde solution.