Versatile Embedded 3D Bioprinting to Create Thick Biomedical Tissue Structures

Creates Complex Thick Tissues Using a Cellular Hydrogel Composite Matrix

This biocompatible matrix bath enables rapid 3D printing of thick tissue analogues with custom features. Tissue engineering is a rapidly growing field that requires advanced fabrication techniques to create permeable thick constructs with specific channels, cavities, and cell compositions similar to tissue. Common thick tissue fabrication procedures are labor-intensive, inefficient, and preclude on-demand feature design, restricting potential for widespread use. Embedded printing processes utilizing cross-linkable matrix materials hold the most promise for rapidly creating constructs with smooth, intricate channel networks. However, tissue matrix materials suitable to these processes are rare, and those available are generally unfit for cell culture applications or lack long-term stability.

Researchers at the University of Florida have developed a flexible, embedded bioprinting process for producing custom biological tissue structures. The polymer-based composite hydrogel matrix bath supports high cell density and retains complex features to enable fabrication of living thick tissue analogues on demand.

Application

Bioprinting matrix bath that forms custom permeable thick tissues for use in disease research, drug development, and in vivo regeneration

Advantages

• Creates custom tissue analogues, supplying biological materials for research, clinical, and personalized therapeutic applications
• Fabricates thick tissues via embedded bioprinting, reducing labor input and improving efficiency
• Controls distribution and density of cells, producing constructs with specialized features
• Supports a range of intricate features and cellular compositions, better mimicking tissue properties

Technology

The matrix bath material is a composite of microgels, a gelatin-based hydrogel precursor, and harvested cells specific to the tissue application. To create features in the matrix bath, an extrusion tip deposits sacrificial material into the composite, forming an intricate filament network. The composite material adjacent to the moving tip liquefies as microgels slide and deform around it, allowing the sacrificial ink to flow out of the extrusion tip smoothly. The microgels then re-solidify upon tip removal, trapping the sacrificial material. After cross-linking the hydrogel matrix, removing the sacrificial material leaves embedded open channels and chambers throughout the composite hydrogel construct. This results in permeable thick tissue analogues once cells inside the matrix reach maturity.