University of Delaware scientists working under Dr. Joel Schneider, associate professor of chemistry and biochemistry, and Dr. Darrin Pochan, associate professor of materials science, developed and patented a novel type of hydrogel, designed to seal wounds and at the same time deliver an antibacterial punch:
Hydrogels are formed from networks of super-absorbent, chain-like polymers. Although they are not soluble in water, they soak up large amounts of it, and their porous structure allows nutrients and cell wastes to pass right through them.
Schneider and Pochan and their research teams have been focusing on developing peptide-based hydrogels that, once implanted in the human body, will become scaffolds for cells to hold onto and grow–cells such as fibroblasts, which form connective tissue, and osteoblasts, which form bone.
“They’re like rebar when you’re building something with concrete,” Schneider said. “They give the cement something to hang onto.”
The basis of UD’s hydrogels is “MAX1,” a self-assembling peptide that the scientists designed six years ago and named after Pochan’s son, Max…
The peptide that Schneider and Pochan and their research teams designed undergoes triggered “self-assembly,” meaning that the peptide will fold automatically into a specific shape in response to a particular trigger, or environmental stimulus, such as exposure to light. After folding, it self-assembles, affording the hydrogel.
Using “MAX8,” the eighth iteration of their original peptide, Lisa Haines-Butterick, a doctoral student in Schneider’s group, figured out how to encapsulate living cells in the hydrogel and then inject the gel into secondary sites without harming the cells.
“Although we have currently only demonstrated this capacity of our gels using simple models, we envision that when injected into the body, the cells encapsulated in the gel can go about their business in restructuring the tissue,” Schneider explained.
UD’s peptide-based hydrogels display several novel features. Not only are they cytocompatible, meaning that they are not toxic to the living cells they are enlisted to deliver, but some of the gels are inherently antimicrobial, killing certain gram-negative and gram-positive bacteria, a characteristic the research team currently is exploring.
The UD hydrogels also can be freeze-dried into a powder and reconstituted into a solution for use. They can be injected from a syringe, offering a minimally invasive approach to medical treatment, as well as a targeted, “leak-proof” way of potentially delivering cells and drugs to a wound or diseased organ.
Collaborations with physicians at Christiana Care Health System in Newark, Del., may lead to future developments for the hydrogels. Schneider recently began working with Dr. Joseph Bennett, a surgeon at the Helen F. Graham Cancer Center who resects liver tumors.
Press release: UD scientists invent novel hydrogels for repairing, regenerating human tissue …
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