The hydrogel material is derived from different-sized seaweed particles. Image: Orlin Velev, NC State University.
The hydrogel material is derived from different-sized seaweed particles. Image: Orlin Velev, NC State University.

Researchers from North Carolina State University (NC State) have shown that 3D-printable gels with improved and highly controlled properties can be created by merging micro- and nano-sized networks of the same material harnessed from seaweed. Their findings could have applications in biomedical materials, such as biological scaffolds for growing cells, and soft robotics.

Reported in a paper in Nature Communications, their findings show that these water-based gels – called homocomposite hydrogels – are both strong and flexible. They are composed of alginates – chemical compounds found in seaweed and algae that are commonly used as thickening agents and in wound dressings.

Merging different-size scale networks of the same alginate eliminates the fragility that can sometimes occur when differing materials are merged together in a hydrogel, says Orlin Velev, professor of chemical and biomolecular engineering at NC State and corresponding author of the paper.

"Water-based materials can be soft and brittle," he said. "But these homocomposite materials – soft fibrillar alginate particles inside a medium of alginate – are really two hydrogels in one: one is a particle hydrogel and one is a molecular hydrogel. Merged together they produce a jelly-like material that is better than the sum of its parts, and whose properties can be tuned precisely for shaping through a 3D printer for on-demand manufacturing."

"We are reinforcing a hydrogel material with the same material, which is remarkable because it uses just one material to improve the overall mechanical properties," said Lilian Hsiao, an assistant professor of chemical and molecular engineering at NC State and a co-author of the paper. "Alginates are used in wound dressings, so this material potentially could be used as a strengthened 3D-printed bandage or as a patch for wound healing or drug delivery."

"These types of materials have the potential to be most useful in medical products, in food products as a thickening agent or in soft robotics," said Austin Williams, one of the paper's co-authors and a graduate student in Velev's lab.

According to Velev, future work will attempt to fine-tune this method of merging homocomposite materials to advance 3D printing for biomedical applications or biomedical injection materials.

"This technique may have uses with other types of gels, like those used in coatings or in consumer products," Hsiao said.

This story is adapted from material from North Carolina State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.