4.5.3 Perfusable tubular filament by optimal process parameters
The aforementioned results demonstrated that the effect of gradient shear stress and cross-linking was proportional to that of the printing pressure, such that the core pore size and shell layer varied with the printing pressure. As shown in Figure 11, the hollow tubular filament was fabricated, and the inner and outer diameters of the tubular gel filament were 316 μm and 1162 μm, respectively. Small diameter and tubular and porous structure (Figure 10) confirmed that we fabricated small-diameter vascular tissue engineering scaffold by 3D bioprinting.