There are simply too many ways our skin can get damaged like cuts, scrapes, blisters, and burns are just a few examples. The usual treatment involves the simple principle of covering the wound with a band-aid or adhesive gauze. This is effective because it does not permit infectious microorganisms to enter into our bloodstream via the skin and also helps in healing.
Recently, advanced wound dressings allow the optimum pH and temperature for healing to be kept in mind as well. But are not common because they can not easily manufacture and supplied since they are expensive and beyond the approach of the public.
To improve and accelerate wound healing, heat-responsive hydrogels are being looked into. Active Adhesive Dressings (AADs) are elastic, strong and antimicrobial. They encourage fast healing of wounds and inhibit the growth of bacteria without further preventive measures. The researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard, the Harvard John A. Paulson School for Engineering and Applied Sciences and McGill University just came across another technique to heal the wounds.
David Mooney is a founding core faculty member of the Wyss Institute and the Robert P. Pinkas Family Professor of Bioengineering at SEAS, speculates how it can also be used for chronic wounds including diabetic ulcers, pressure sores, for drug delivery and as components of soft robotics-based therapies.
The inspiration for creating AADs comes from developing embryos, whose skin has the capacity to completely heal without forming a scar. The embryonic skin cells produce actin fibers around the wound and pull its edges closer, similar in mechanism to a drawstring pouch being closed. Once the fetus develops pass a certain point, this characteristic is sadly lost, and healing involves inflammation and scarring.
To mimic this beautiful mechanism of nature, scientists added thermoresponsive polymer PNIPAm to the hydrogels, which is hydrophobic and shrinks at 90 degrees Fahrenheit. The result is a hybrid hydrogel which contracts when exposed to body heat, transferring the forces of the contracting polymer to the tissue beneath through strong bonds between the tissue and the hydrogel. As well as this, AAD has silver nanoparticles embedded in it, which offer protection against microbes.
Benjamin Franklin is a post-doctoral fellow in the Mooney lab and a leader in the project. He exclaims that AAD has 10 times the binding strength of usual Band-Aid and preventing bacterial growth. Ignoring its wound-closing properties, this invention is still a lot better than ordinary first-aid products.
Researchers tested AAD on patches of mouse skin and were pleased to discover that wound area size reduced by 45 percent and healer much faster than not treated or treated with microgels, chitosan, gelatin, and other hydrogels. AAD is safe for use on living tissue as it causes no swelling or immune response. Researchers are also able to adjust the amount of the wound closed with AAD by modifying the amounts of acrylamide monomers while manufacturing.
Co-first author Jianyu Li commented on how this particular property could prove useful upon application to the elbow area, which requires movement compared to the static areas like the shin. Jianyu Li is a former postdoctoral fellow at the Wyss Institute and presently holds a post as an assistant professor at the McGill University.
The team also computerised wound closure with the help of AAD and predicted that it causes human skin to contract at a comparable rate to that of the mouse. This shows that it has higher chances of showing clinical benefit in the case of humans.
The research continues along with studies that help to learn further about how AAD mechanically affects the bioprocess of healing and how it is affected by body temperature and body locations. Additional studies revolve around AAD’s future in medicine, and whether it is worth commercialization.
Aniqa Mazhar is a graduate of QAU in Biochemistry. She has taught sciences to O levels and is currently planning for her MS in Food Technology. Aniqa’s hobbies are reading, watching movies, writing, calligraphy, long walks, and nature photography.