Preparation and properties of composite hydrogels for 3D bioprinting

Bioprinted scaffolds have broad applications in the treatment of cardiovascular diseases. 3D bioprinting can prepare complex structures and shapes, and the fabrication of high-performance bioinks is the key to technological progress. This study selected gelatin, chitosan quaternary ammonium salt, and sodium cromoglycate as substrates to design and characterize two groups of hydrogel materials for bioprinting. Two hydrogels were prepared by extrusion bioprinting: Gel/HACC/DSCG hydrogel and GelMA/HACC-DSCG hydrogel. The physicochemical and liquid crystal properties of hydrogels were characterized. The effect of liquid crystal on cell proliferation and orientation was evaluated by culturing human umbilical vein endothelial cells. The Gel/HACC/DSCG hydrogels showed inducibility to orientated cell growth. The GelMA/HACC-DSCG hydrogels had lesser damaged cells and stronger mechanical strength and stability in printing, however, the liquid crystal properties were weakened, and the effect on cell growth orientation was not significant.