Preparation and characterization of a new sustainable bio-based elastomer nanocomposites containing poly(glycerol sebacate citrate)/chitosan/n-hydroxyapatite for promising tissue engineering applications.

Poly (glycerol sebacate citrate) (PGSC) has potential applications in tissue engineering due to its biodegradability and suitable elasticity. However, its applications are restricted owing to its acidity and high degradation rate. In this study, a new bio-nanocomposite based on PGSC has been synthesized by incorporating chitosan (CS) and various concentrations of hydroxyapatite nanoparticles (n-HA). It is assumed that the basicity of a CS and hydroxyl groups of n-HA will reduce the acidity of PGSC and control the rate of degradation. Also, the biocompatibility of n-HA and inherent hydrophilicity of CS can improve cell adhesion and proliferation of PGSC-based scaffolds. FTIR, XRD, FESEM, and EDX tests confirmed the synthesis of these nanocomposites and the interaction between each of the components. The results of the DMTA test also indicated the elastic behavior of the samples embedded with n-HA. The hydrophilicity assay demonstrated that the water contact angle of the scaffolds decreased as the concentration of n-HA augmented, and it reached the value of 44 ± 0.9° for nanocomposite containing 5 wt.% n-HA. The degradation rate of all PGSC nanocomposites was reduced due to the anionic groups of n-HA and CS. TGA assay indicated that the incorporation of n-HA led to the enhancement of scaffolds' thermal stability. Furthermore, the synergistic effect of CS and n-HA on the enhancement of protein adsorption and cell proliferation was confirmed through protein adhesion and MTT assay, respectively. Consequently, the addition of n-HA and CS perform the new bio-nanocomposites scaffolds based on PGSC with sufficient hydrophilicity, flexibility, and thermal stability in tissue engineering applications.