University of Colorado Boulder team 3D prints adhesive elastic materials for tissue repair and more | VoxelMatters

A research team from the University of Colorado at Boulder (CU Boulder) and the University of Pennsylvania has pioneered a process for 3D printing hydrogel materials that are simultaneously stretchy, adhesive and resilient, which could be used to print internal bandages to repair damaged heart tissue, cartilage patches or needle-free sutures.

Jason Burdick, senior author on the research paper and professor of chemical and biological engineering at the University of Colorado at Boulder, said of the work: “Cardiac and cartilage tissues are similar in that they have a very limited ability to repair themselves. When they are damaged, there is no going back. By developing new, stronger materials to enhance that repair process, we can have a huge impact on patients.”

Interestingly, the innovative research project, which was recently published in the journal ScienceThe company took inspiration from a somewhat unexpected place: worms, whose bodies can join together to become an intertwined mass with both solid and liquid properties. In the scientific world, this is known as a “worm blob.” This concept was translated by integrating intertwined chains of molecules, or tangles, into the 3D printing material.

The creation of this tough, Band-Aid-like material is made possible by a specific 3D printing process developed by the research team. This process, known as CLEAR (Continuous Curing After Light Exposure Assisted by Redox Initiation), controls the entanglement of the material’s molecules as it is printed. This is done through a combination of “light and dark polymerization.” As the researchers write: “This generalizable approach achieves high monomer conversion at room temperature without the need for additional stimuli such as light or heat after printing, and enables the additive manufacturing of highly entangled hydrogels and elastomers that exhibit four to seven times higher extension energies compared to those of traditional DLP.”

This technology, for which the researchers have filed a provisional patent, has not only managed to print materials that are more flexible and stronger than parts printed on standard DLP machines, but are also adhesive, allowing them to stick to fabric. Matt Davidson, a research associate in Burdick’s lab, says this capability is a first: “We can now 3D print adhesive materials that are strong enough to mechanically support fabric. We’ve never been able to do that before.”

The next steps in the research will be to study how these 3D printed materials interact with organic tissues, and the researchers hope that in the future their innovative solution will be used to help treat patients with heart defects, support tissue regeneration by delivering drugs directly to organs or cartilage, and more.

Applications of this 3D printing process could also be used in other sectors, such as research and development and manufacturing. According to the CU Boulder team, other research teams and industrial end users might be interested in the CLEAR process because it requires no additional energy to cure parts. “This is a simple 3D processing method that people could use in their own academic labs as well as in industry to improve the mechanical properties of materials for a wide variety of applications. It solves a big problem for 3D printing,” explained first author Abhishek Dhand, a researcher in the Burdick lab and a PhD candidate at the University of Pennsylvania.