Advancing bioinks for 3D bioprinting using reactive fillers: A review

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Biofabrication

Background:

• Growing demand for personalized implants and tissue scaffolds necessitates advanced biomaterials.
• 3D printing of cell-laden hydrogels (bioinks) shows promise for fabricating complex tissue structures.
• Polymeric hydrogels often exhibit poor stability and printing fidelity, driving the development of multi-material bioinks.

Purpose of the Study:

• To review the state-of-the-art of composite bioinks incorporating inorganic bioactive fillers for 3D bioprinting.
• To analyze the impact of these fillers on bioink properties, printability, and cellular behavior.
• To discuss the progress, challenges, and future research directions in this field.

Main Methods:

• Literature review of composite bioink systems containing polymeric hydrogels and inorganic bioactive fillers.
• Analysis of studies reporting on bioink properties, printability, and cytocompatibility.
• Evaluation of the effect of fillers like silicates and calcium-phosphates on 3D construct characteristics.

Main Results:

• Composite bioinks with inorganic fillers demonstrate substantially improved bioprinting characteristics compared to pure hydrogels.
• Bioactive fillers enhance stability, printing fidelity, and cytocompatibility of 3D bioprinted constructs.
• Inorganic fillers provide functionalities such as in-situ crosslinking and mineralization, promoting cell viability and tissue regeneration.

Conclusions:

• Bioactive composite bioinks are a promising approach for fabricating stable 3D tissue constructs for regeneration.
• Inorganic fillers offer enhanced properties and functionalities crucial for advanced biofabrication.
• Further functionalization with drugs or growth factors can lead to specialized biomedical therapies.