A Handheld 3D Bioprinter for in situ Tissue Regeneration

Restricted (Penn State Only)
- Author:
- Hjaltason, Anton
- Area of Honors:
- Chemical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Amir Sheikhi, Thesis Supervisor
Scott Thomas Milner, Thesis Honors Advisor - Keywords:
- Tissue Engineering
Regenerative Medicine
Handheld 3D Bioprinting - Abstract:
- In the field of tissue engineering, three-dimensional (3D) bioprinting has emerged as a novel approach to make hydrogel scaffolds in situ with a variety of shapes and sizes. This method involves the extrusion of cells and biomaterials in filaments, enabling layer-by-layer scaffold deposition, followed by photo-mediated crosslinking. Its versatility makes it uniquely suited for personalized tissue regeneration, where patient-specific hydrogel scaffolds may be applied to wound areas with irregular shapes. One caveat of current 3D bioprinters on the market is that they are typically desktop systems. While these devices can fabricate many scaffold shapes with high fidelity, it is difficult for the computer system to exactly match the complex geometries seen in many wounds. Handheld 3D bioprinters can resolve this issue by directly depositing bioinks onto an area of the body. Handheld bioprinters currently exist on the market and in the laboratory, but many are unergonomic, require bulky external equipment, or lack specific flow rate control. This project involves the design and testing of a new handheld 3D bioprinter that can print a gelatin methacryloyl (GelMA)-based granular bioink in situ. Granular bioinks have been developed to solve the challenge of nanoporous bulk hydrogels by taking advantage of the void space among microscale hydrogel particles (microgels). These microgels can be mixed with nanoparticles and a photoinitiator to make a nanoengineered granular bioink, NGB, which is then 3D bioprinted into a scaffold. The design of the handheld bioprinter developed in this project includes a mechanical piston extrusion system, specific flow rate control, and a small form factor. The goal of these experiments is to combine the technology of handheld 3D bioprinting with NGB to bring this new bioink into surgical settings in the future. The results indicate that the handheld bioprinter is simple and inexpensive to manufacture. Additionally, it can print NGB somewhat effectively and shows promise for future experiments with the granular bioink.