Table 4.

Ink features for 3D bioprinting of human tissue. Table modified with permission from reference [12].

Printability	Physicochemical properties (surface tension, viscosity, crosslinking) of the ink that allows its spatial and temporal deposition with high precision and accuracy during the printing process.
Biocompatibility	The ability of the ink to support normal cellular activity (cell attachments and proliferation) without causing an inflammatory or immune response to the host tissue.
Biodegradability	The ideal degradation rate of ink is matching the ability of cells to replace the ink material with their extracellular matrix proteins. Degradation by-products should be harmless and easily metabolized from the host.
Mechanical property	Bioinks should provide the required tensile strength, stiffness, and elasticity for mimicking the mechanical properties of native bone tissues and provide the cells with a stable environment for attachment, proliferation, and differentiation.
Material biomimicry	Engineering bioink material with specific physiological functions requires mimicking the naturally tissue-specific composition and localization of extracellular matrix components in the human tissue.