Extrusion Bioprinting of Scaffolds for Tissue Engineering Applications

Freeze drying (lyophilization) is a tissue engineering technique involving freezing, primary drying (sublimation), and secondary drying (desorption) to create scaffolds with specific geometries, particularly useful for organ-specific scaffolds.

“Freeze drying, also known as lyophilization, is a technique used in tissue engineering to create scaffolds with specific geometries. It involves three main stages: freezing, primary drying (sublimation), and secondary drying (desorption). This method is particularly useful for generating organ-specific scaffolds that can support tissue development and repair (Figure 12B) [269].”

An ideal gas foaming method avoids surfactants and organic solvents, making it suitable for biomedical applications.

“Importantly, an ideal gas foaming method avoids the use of surfactants and organic solvents, making it suitable for biomedical applications (Figure 12A) [269].”

Melt molding with porogen leaching is a nonsolvent fabrication method that allows independent control over scaffold morphology and shape.

“Melt molding with porogen leaching is a nonsolvent fabrication method that allows for independent control over the scaffold’s morphology and shape [269].”

Phase separation creates tissue engineering scaffolds with tailored mechanical properties and controlled pore sizes by dissolving biodegradable polymers, inducing phase separation, solidifying the polymer-rich phase into interconnected pores, washing residual solvents, and seeding cells.

“Phase separation is a technique used in tissue engineering to create scaffolds with tailored mechanical properties and controlled pore sizes. This technique in tissue engineering involves several key steps to develop scaffolds with tailored properties. Initially, suitable biodegradable polymers (either natural or synthetic) are selected and dissolved in a solvent to form a homogeneous solution.”

Gas foaming is a cost-effective tissue engineering technique that can achieve porosity up to 90% by nucleation and growth of gas bubbles within a polymer.

“Gas foaming is a technique used in tissue engineering to create porous structures, especially in hydrogels. This method is cost-effective and can achieve high porosity levels up to 90%. It involves the nucleation and growth of gas bubbles within a polymer, which forms an internal phase where porosity is introduced.”