Wound Healing.
A group of researchers From The Hong Kong Polytechnic University (PolyU) has designed an innovative "bionic cooling skin" which has the potential to revolutionize the treatment of infected wounds. The wound dressing material also has cooling effects, antibacterial properties and skin-like flexibility which not only shortens but also improves the healing process of damaged tissues.
There are a number of limitations with traditional wound dressings. Gauze can stick to the wound, causing pain when removed, foam dressings are costly and hydrocolloid dressings are not ideal for infected wounds. The majority of products available today make a compromise between comfort, protection and antibacterial. To fill this void a new bionic skin has been developed that combines a number of functions. The material is claimed to be like human skin and actively promotes healing rather than merely protecting the wound.
The dressing is made up of two-layer "Janus" nanofiber structure. The outermost layer is water repellent and will reflect the sun's heat to help cool the wound site. The inner layer is composed of Fe-ZIF8 nanoparticles and absorbs moisture. These nanoparticles are effective at killing bacteria when exposed to visible light. The photocatalytic activity helps the dressing to control infection without being totally dependent on antibiotics. It also has a high infrared emissivity to release extra heat and keep the wound temperature cooler helping the healing process even more.
The scientists revealed a number of encouraging findings published in Springer in which the bionic skin demonstrated excellent air permeability and moisture management properties including a particle filtration efficiency over 99.8 per cent. The dressing lowered surface temperature by approximately 4 C under simulated sunlight compared with non-Janus materials. In animal studies wounds covered with the bionic skin stayed about 1.7 degrees cooler in outdoor conditions.
Significantly the dressing was shown to be 97.1 per cent effective at killing the Staphylococcus aureus bacterium which is a common cause of wound infection. What was most remarkable about these findings was the near complete closure of wounds treated with the dressing within 11 days. The healing rate was over twice the rate of untreated wounds or wounds treated with traditional materials.
Analysis of the gene showed that the dressing has a beneficial effect on several healing pathways. It boosted the expression of genes that are important for the formation of new blood vessels and blood cells that move to the site of injury and are involved in tissue repair.
Concurrently, it increased antimicrobial peptides and decreased inflammatory factors such as Tumour Necrosis Factor-Alpha (TNF-alpha). Additionally important pathways involved in wound healing such as PI3K-Akt and HIF-1 and NF-kappa B pathways were also activated.
The bionic cooling skin represents a new generation of intelligent wound dressings. The combination of cooling, anti-bacterial and tissue regeneration properties in a single material. It provides an excellent environment for infected wound healing. The results indicate that future treatments for wounds could allow skin to heal and repair wounds in addition to preventing them from being damaged.
Disclaimer: This article is for informational purposes only and is based on preclinical research. The dressing is not yet a standard treatment and requires further clinical validation.
