3D printed self-healing hydrogels

Researchers have developed a printable hydrogel that is able to self-heal using light, and which could have wide-ranging applications in medicine, soft robotics and energy storage.

Self-healing (SH) hydrogels have so far only been processed using extrusion-based additive manufacturing technology, which has limited the complexity of what can be printed. The new hydrogel, developed by a team at the Politecnico di Torino in collaboration with the Hebrew University of Jerusalem, instead relies on a digital light processing (DLP) 3D printer. This enables the creation of the complex architectures required in areas such as regenerative medicine.

Described in Nature Communications, the SH hydrogel is created using only commercially available materials and an off-the-shelf DLP printer. According to research coordinator Ignazio Roppolo, from the Politecnico’s MP4MNT (Materials and Processing for Micro and Nanotechnologies) team, a light-activated SH hydrogel is something that he and his colleagues have been chasing for some time, and has the potential to enhance multiple applications in medicine and beyond.

"Since many years in the MP4MNT group, a research unit coordinated by Dr Annalisa Chiappone and I is specifically devoted to development of new materials that can be processed using 3D printing activated by light,” said Roppolo.

“3D printing is able to offer a synergistic effect between the design of the object and the intrinsic properties of materials, making possible to obtain manufactured items with unique features. From our perspective, we need to take advantage of this synergy to best develop the capabilities of 3D printing, so that this can truly become an element of our everyday life. And this research falls right in line with this philosophy.”

The researchers believe the work represents a first step towards the development of highly intricate 3D printed forms, bringing complex geometries and intrinsic self-healing properties to various fields. In particular, following the completion of biocompatibility studies of the SH hydrogel, the team hopes to roll out basic research into cellular mechanisms as well as applications in regenerative medicine.