Designing vascular supportive albumen-rich composite bioink for organ 3D printing.

Bioink plays a major role in 3D printing of tissues and organs. Alginate is a widely used component for bioinks but its cellular responses are limited, which limits its clinical translation. In this study, we demonstrate the printability and cellular compatibility of composite bioink consists of sodium alginate (NaAlg) and egg white, also called albumen. The experimental conditions necessary for 3D printing composite bioink were optimized by changing different concentration ratios of Albumen/NaAlg and their various physicochemical properties were studied. The structural characteristics of the 3D printed scaffold was also investigated. In vitro experiments showed that human umbilical vein endothelial cells can successfully attach to the printed scaffold and maintain high viability during the course of study. Interestingly, vascular sprouting and neovascular network formation was observed inbetween fibers within the printed scaffold. In conclusion, the results of this study demonstrate that 3D printed Albumen/NaAlg composite bioinks with favorable biological functionality hold a great potential in tissue and organ engineering.