Proteins Sensitive To Stimuli Could Be The Key For Wound Healing

Hydrogels could one day play a major role in the wound healing process. Those that comprise stimuli-sensitive polymers cans serve as good molecular scaffolds because of their advantages in tissue engineering, drug delivery and various other applications. Peptides and proteins are chosen as building blocks because of their innate ability to assemble into nanostructures when stimulated.

Such nanoparticles or nanofibers enable gelation, which is the formation of supramolecular hydrogels that have the ability to trap water and other small molecules. Engineers are using these types of materials to develop systems that can respond to various stimuli such as heat, pH, light, ionic strength, redox and several others.

Researchers at the NYU Tandon School of Engineering, who previously identified a responsive hydrogel formed by the use of coiled-coil protein, Q, are now expanding their work. They are looking into the gelation of Q protein at defined temperatures and pH conditions. This works as an off/on switch to tell the particles when and what to do.

Jin Kim Montclare, professor of chemical and biomolecular engineering, with affiliations at NYU Langone Health and NYU College of Dentistry, directed this research with first author Michael Meleties, fellow Ph.D. student Dustin Britton, postdoctoral associate Priya Katyal, and undergraduate research assistant Bonnie Lin.

Photo Credit: Diana Polekhina from Unsplash

The team used transmission electron microscopy, rheology and structural analyses to observe that Q self-assembles and forms fiber-based hydrogels. They seem to show upper critical solution temperature (UCST) behavior with higher elastic properties at pH 7.4 and pH10. However, at pH6, Q forms polydisperse nanoparticles that do not self-assemble or form a gelation.

This is because at said pH, the high net positive charge causes significant electrostatic repulsion that prevents gelation. The researchers say that these findings may pave the way for the development of novel scaffolds and functional biomaterials that are sensitive to certain stimuli.

“In our case, it is due to the physical crosslinking/entanglement of fibers that our fiber-based hydrogel forms when cooled, when the temperature is raised above the critical temperature, the hydrogel transitions back into solution and most of the fibers should disentangle, said Montclare.”

These findings could someday help develop better tools for wound healing. If we are able to attach a certain polymer to the surface of a wound or burn and stimulate gelation, that could help the body heal without having to use bandages or plasters.