Table 3.

Rheological tests to characterize properties of bioinks (Note: All the tests are supposed to performed based on the samples that passed through sterilization. When cells are involved, comparison between non‐cell bioinks and cell‐laden bioinks is recommended)

Rheological tests	Variable	Output
Amplitude sweep	Strain (γ)	Storage modulus (G’), loss modulus (G’’)
Frequency sweep	Frequency (f, or ω)	G’ and G’’
Temperature sweep From high temperature (T H) to low temperature (T L) or from T L to T H Temperature change during printing	Temperature (T)	G’ and G’’, or viscosity (η)
Shear rate sweep	Shear rate (γ̇)	G’ and G’’, or η
Time sweep At holding temperature	Time (t)	G’ and G’’, or η
Yield stress Simulating bioink passing through pipes with different diameters	γ̇	Shear stress (σ)
Strain–stress (compressive)	Compressive strain (γ)	Normal force (N)