Chitosan-Gelatin/Biphasic calcium phosphate composite scaffold for bone tissue engineering: Optimization of mechanical properties with the statistical model

Biphasic calcium phosphate not only does have good mechanical properties for using in bone tissue engineering، but also has desirable osteoconductivity. In this study، composite scaffolds based on chitosan-gelatin / Biphasic calcium phosphate were fabricated. Synthetic of scaffolds، mechanical testing and modeling of the compressive strength in order to achieve the optimized sample were objectives of this research. Ceramic phase was synthesized using the microwave. The ratio of gelatin to chitosan was fixed according to previous research. XRD was used In order to identify the phases and calculate the amount of each phase in ceramic. To determine the chemical composition of the powder Fourier transform infrared spectroscopy (FTIR) was used. The results confirmed the presence of 68% HA in ceramic phase. Five samples with different ceramic phase in 15 tests were designed. Freeze drying was used to prepare scaffolds. chemical Composition of scaffolds using FTIR and size and morphology of pores using Scanning Electron Microscope were determined. Final scaffolds، proportional to the ceramic phase، contain 30 to 81% porosity with an average pore size of 119 to 265 micrometers. Mechanical properties of Scaffold have also studied and suggested that with the increasing of ceramic phase، Young’s modulus، yield strength and compressive strength will increase، and Average pore size and percent of porosity will decrease. Rheological properties of the scaffolds were analyzed by statistical analysis، mathematical relation between the ceramic phase and each of the properties were calculated and with integrating two models of the Young''s modulus and porosity، scaffold with 68% ceramic phase was estimated as the optimum sample.