The Royal Australian University of Technology has developed a new 3D printing technique that allows the creation of tiny biomedical implants. The technique consists of printing glue molds that are then filled with biomaterial. Once the mold dissolves, the structure of the biomaterial remains. This is achieved thanks to 3D printers like those now commonly found in high schools, using polyvinyl acetate as the printing material.
Although printing for tissue replacement is a very large research area, but all teams around the world have worked hard to create very complex structures that could help improve the viability of printed implants. Tissues are naturally complex, but at the moment 3D printed biomaterials are somewhat complex in terms of resolution and complexity. These researchers realized that printing a reverse shape could be a better approach when looking to create more complex structures.
The complexity of these implants
Cathal O’Connell, a researcher involved in the study, noted that the shapes that can be made using a 3D printer are limited by the size of the print nozzle, as the opening must be large enough to allow material to pass through and Ultimately, that influences the size you can print.
“But the gaps between the printed material can be much smaller. By changing our thinking, we essentially draw the structure we want in the empty space inside our 3D printed mold. This allows us to create tiny and complex microstructures where cells will thrive ”he added.
Researchers have called this printing technique NEST3D . The ink used for printing is glue that is commonly used by children in schools to do simple construction jobs. In fact, the 3D printer the researchers use has relatively low specifications, which they describe as “high school grade.”
A breakthrough for tissue engineering
It should be noted that this technique is versatile enough to use commercially available medical grade materials. Being able to create such complex shapes with a high school grade 3D printer is something extraordinary. This lowers the bar for entering this field of work and involves taking a significant step toward making tissue engineering a medical reality.
Printed structures can be dissolved from the core of the biomaterial simply by placing them in water. The key is that an injection molding technique is used in its versatility. Another of the researchers involved in the study, Stephanie Doyle, has stated that they can produce dozens of test samples in different varieties of materials, such as biodegradable polymers, silicones, hydrogels or ceramics, without the need for rigorous optimization or specialized equipment.
Researchers have been able to produce 3D structures that can be 200 microns wide, equivalent to the width of four human hairs, and with a complexity that rivals that which can be achieved by light-based fabrication techniques. This could massively accelerate research in biofabrication and tissue engineering.