Preparation and Characterization of 3D Printed dECM/GelMA/NC/SA Tissue Engineered Hybrid Scaffold

At present, in vitro colorectal tumor model has received extensive attention. Among them, decellular matrix (dECM) is widely used in the preparation of tissue engineering scaffolds due to its excellent biocompatibility, low immunity and natural three-dimensional structure. Among them, there are abundant capillaries and lymphatic capillaries in the villi of the fold on the inner surface of the small intestine of pigs, which is conducive to the absorption of nutrients. In this experiment, physical, chemical and biological enzyme methods were combined to decellularize pig small intestine to obtain dECM. SEM and histochemical staining proved that the microstructure of the tissue was not destroyed and the cells were effectively removed after decellularization. Two kinds of hydrogel scaffolds were prepared by 3D extrusion bioprinting using dECM, methacrylated gelatin (GelMA), sodium alginate (SA) and nano-clay (NC). The mechanical properties, microstructure and biocompatibility of scaffolds were characterized. The results showed that dECM can reduce the pore size of the scaffold, improve the mechanical strength of the scaffold, and facilitate cell adhesion, growth, proliferation, migration and aggregation. dECM/GelMA/SA/NC scaffold is expected to provide a promising platform for the construction of colorectal tumor models in vitro.