A coaxial 3D bioprinted hybrid vascular scaffold based on decellularized extracellular matrix/nano clay/sodium alginate bioink.

Currently, vascular grafting is the preferred option to replace or bypass the defective vascular segments, but finding materials with good biocompatibility and diversity alternative for practical clinical applications are still the challenge. The construction of tissue engineered blood vessels (TEBVs) with complex structures will be realized using 3D bioprinting technology, which provides a new idea for vascular transplantation. In this paper, the decellularized extracellular matrix (dECM)/nano clay (NC)/sodium alginate (SA) hybrid bioink was prepared to construct tubular scaffolds in vitro by coaxial 3D bioprinting. The physical properties of the tubular scaffolds showed that there were plenty of pores, of which the size was ranged from 5 μm to 100 μm. Among them, the 2d/NC/SA scaffold not only has good hydrophilicity (>300 %), good biomechanical properties (tensile strength: 0.99 ± 0.01 MPa, Young's modulus: 0.61 ± 0.02 MPa) and low hemolysis ratio (0.3 %), but also can effectively enhance cell adhesion and proliferation. Cell experiment also showed that the cell density and cell colonies were large and more on the coaxial printed tubular scaffolds compare to those on the 3D printed lamellar scaffolds, and the 2d/NC/SA tubular scaffold has the best bioactivity of tunica intima model. Overall, the advanced dECM/NC/SA tubular scaffold has a considerable potential to be applied in vascular tissue engineering.