3D Printing Of Type Ⅰ Collagen/true Bone Ceramic/GelMA/alginate Composite Auricular Cartilage Scaffold And The Study Of Its Physical And Chemical Properties

Background:The auricle plays an important role in facial aesthetics and identity cognition.External ear reconstruction is not only a difficult point in plastic surgery,but also a hot spot in cartilage tissue engineering research.The rapid development of tissue engineering provides new ideas for the reconstruction of the external ear,and the research of new materials is one of the focuses of tissue engineering research.3D printing technology provides the possibility to construct a composite scaffold with highly individual appearance,suitable microstructure and porosity,good mechanical properties and biocompatibility.Objective:To prepare typeⅠcollagen/true bone ceramic/GelMA/alginate composite auricular cartilage scaffold by 3D printing technology and study its physical and chemical properties.Methods:The parameters in the process of 3D printing were optimized through experiments.Using 3D printing and freeze-drying technology,the composite materials were made into scaffolds with ear shape,and the porosity,density,mechanical properties,scanning electron microscopy and infrared spectroscopy of the scaffolds were measured.Results:The experiment shows that when the printing speed is 30mm/s,the extrusion ratio is 1.5,the infill extrusion width is 150%,and the temperature of the cryogenic deposition platform is set at 4℃,the ideal printing effect can be obtained.The composite scaffold density and porosity are(0.2887±0.0291)g/cm~3 and(82.67±2.14)%,respectively.The elastic modulus is(1.8067±0.1443)MPa,the compressive strength is(72.4333±0.4922)MPa,the maximum compression load is(3633.3333±121.1977)N,and the compression strain at the maximum load point is(22.6667±3.5921)%.The scaffold has clear outline and lifelike appearance.Bending test shows that the scaffold has certain macroscopic elasticity and strength.SEM results shows that the pore size of the scaffold is regular,the permeability is good,and the micropore size is about30～50μm.Infrared spectrum analysis of the composite scaffold suggests the presence of typeⅠcollagen,true bone ceramic,GelMA and alginate.Conclusions:1.The typeⅠcollagen/true bone ceramic/GelMA/alginate composite auricular cartilage scaffold were successfully prepared;2.The physical and chemical properties of the composite auricular cartilage scaffold prepared meet the requirements of ideal auricular scaffold.