The team at McGill University in Canada said their so-called ‘sonogel’ technique is a faster, cleaner and more sustainable approach to hydrogel fabrication. Furthermore, it produces hydrogels that are stronger, more flexible and highly resistant to freezing and dehydration. The new method also promises to facilitate advances in tissue engineering, bioadhesives and 3D bioprinting. The team’s findings are detailed in Advanced Science.
Hydrogels are composed of polymers that can absorb and retain large amounts of water and find use in wound dressings, drug delivery, tissue engineering, soft robotics, soft contact lenses and more.
Traditional hydrogel manufacturing relies on chemical initiators that trigger chemical chain reactions.
In collaboration with Polytechnique Montréal, the McGill research team, led by mechanical engineering Professor Jianyu Li, has developed an alternative method using ultrasound. When applied to a liquid precursor, sound waves create microscopic bubbles that collapse with immense energy, triggering gel formation within minutes.
“The problem we aimed to solve was the reliance on toxic chemical initiators,” Li said in a statement. “Our method eliminates these substances, making the process safer for the body and better for the environment.”
“Typical hydrogel synthesis can take hours or even overnight under UV light,” said Li. “With ultrasound, it happens in just five minutes.”
According to the team, one application for this technology is in non-invasive medical treatments; because ultrasound waves can penetrate deep into tissues, this method could enable in-body hydrogel formation without surgery.
“Imagine injecting a liquid precursor and using ultrasound to solidify it precisely where needed,” said Li. “This could be a game-changer for treating tissue damage and regenerative medicine. [With] further refinement, we can unlock new possibilities for safer, greener material production.”
The technique could also lead to ultrasound-based 3D bioprinting where instead of relying on light or heat, researchers could use sound waves to precisely ‘print’ hydrogel structures.
“By leveraging high-intensity focused ultrasound, we can shape and build hydrogels with remarkable precision,” said Jean Provost, one of co-authors of the study and assistant professor of engineering physics at Polytechnique Montréal.
