With aging populations and increasing rates of diabetes, the prevalence of chronic wounds is on the rise, putting many patients at risk for amputations. Researchers at UC Riverside have developed an innovative gel that delivers oxygen, potentially healing wounds that might otherwise lead to limb loss.
Understanding Oxygen Deprivation
Chronic wounds, defined as injuries that fail to heal within a month, impact approximately 12 million people globally each year, with around 4.5 million in the United States alone. Alarmingly, about 20% of these individuals may face life-changing amputations.
The new gel, tested in animal studies, addresses a primary cause of many chronic wounds: insufficient oxygen in the deeper layers of damaged tissue. Without adequate oxygen, wounds linger in a state of inflammation, allowing bacteria to thrive and preventing tissue from regenerating.
“Chronic wounds don’t heal on their own,” explained Iman Noshadi, an associate professor of bioengineering at UCR and the lead researcher.
He further stated, “There are four stages to healing chronic wounds: inflammation, vascularization where new blood vessels form, remodeling, and regeneration. A stable oxygen supply is crucial during any of these stages.” When oxygen from air or blood doesn’t reach deep into the injured tissue, it results in hypoxia, which disrupts normal healing. The researchers outlined their approach to combat hypoxia with this gel in a recent paper published in Communications Materials.
Innovative Oxygen Delivery System
The gel itself is soft and flexible, containing both water and a choline-based antibacterial liquid that is safe for living tissue. When connected to a small battery, similar to those in hearing aids, the gel operates as a micro electrochemical device that splits water molecules and generates a consistent flow of oxygen.
Unlike surface treatments, this gel adapts to the unique shape of each wound, ensuring that even the hardest-to-reach areas receive oxygen. Before it hardens, the material molds to the contours of the damaged tissue.
Moreover, the oxygen delivery is continuous. Given that vascularization can take weeks, intermittent oxygen doses wouldn’t suffice. This new system can maintain stable oxygen levels for up to a month, enabling a nonhealing wound to behave like a typical injury.
Animal Testing Results
Tests conducted on diabetic and older mice, whose wounds are similar to those of aging humans, showed that untreated injuries often remained open and could be fatal. However, with the oxygen-generating patch applied and changed weekly, wounds completely healed in about 23 days, and the mice survived.
“We could potentially market this patch as a product, though the gel may need replacing from time to time,” remarked Prince David Okoro, a bioengineering doctoral candidate at UCR and co-author of the study.
Additionally, the gel’s chemistry brings another advantage. Choline, a main ingredient, helps to modulate the immune response, which can reduce excessive inflammation. Chronic wounds often face an overload of reactive oxygen species—unstable molecules that damage cells and prolong inflammation. By enhancing stable oxygen while curbing immune overreactions, the gel aims to restore balance, rather than exacerbate stress.
“While some bandages can absorb fluids or release antimicrobial agents, none directly address hypoxia, which is a fundamental issue we’re confronting,” added Okoro.
Future Beyond Wound Care
The implications of this research go beyond just addressing wounds. Oxygen and nutrient deprivation is a significant obstacle in efforts to grow replacement tissues or organs, which is a key objective in Noshadi’s lab.
“As tissue thickness increases, it becomes challenging to supply cells with the necessary nutrients, leading to cell death,” Noshadi pointed out. “This project could pave the way for creating and sustaining larger organs for those in need.”
However, factors contributing to chronic wounds can’t all be dealt with through a gel. Rising diabetes rates and aging populations play a role, as do lifestyle choices. UCR bioengineer and co-author Baishali Kanjilal noted, “Sedentary lifestyles are weakening our immune responses. It’s complicated to address the societal roots of these challenges, but this innovation presents an opportunity to lessen amputations, enhance life quality, and provide the body what it needs to heal effectively.”
