Researchers at the Hong Kong University of Science and Technology have developed a light-sensitive hydrogel that could be useful for drug delivery.
Conventional materials for hydrogel scaffolds include synthetic polymers or natural biomolecules. This leaves the material to exist as a passive scaffold that can’t interact with the signals involved in biological processes.
Instead, this team of scientists focused on creating a hydrogel that is responsive to light. Light could be particularly useful in biomedical applications, since it could control cell behavior with minimal invasiveness and great precision. The team said it focused on addressing challenges relating to the assembly of complex globular proteins into supramolecular architectures.
In a study published in PNAS, the researchers described how they integrated stimuli-responsive proteins directly into a B12-dependent, light-sensitive hydrogel.
“In our research, we were able to create an entirely recombinant protein-based light-sensitive hydrogels by covalently assembling the CarHC photoreceptor proteins using genetically encoded SpyTag-SpyCatcher chemistry,” author Fei Sun said in prepared remarks. “The AdoB12-dependent CarHC tetramerization has been shown to be essential for the formation of an elastic hydrogel in the dark, which can undergo a rapid gel-sol transition caused by light-induced CarHC disassembly.”
“The resulting hydrogel composed of physically self-assembled CarHC polymers exhibited a rapid gel-sol transition on light exposure, which enabled the facile release/recovery of 3T3 fibroblasts and human mesenchymal stem cells (hMSCs) from 3D cultures while maintaining their viability.” Sun added. “Given the growing demand for creating stimuli-responsive ‘smart’ hydrogels, the direct assembly of stimuli-responsive proteins into hydrogels represents a versatile strategy for designing dynamically tunable materials.”