A Breakthrough Gel For Wounds That Refuse To Heal

Scientists at the University of California, Riverside (UCR), have developed an innovative oxygen-delivering gel that may offer new hope for chronic wounds, like those due to diabetes.

These are injuries that fail to heal within four weeks, often lingering for months and dramatically increasing the risk of infection, hospitalization, and even limb amputation.

Globally, nearly 12 million people suffer from chronic wounds each year. Alarmingly, about 20% of these patients ultimately undergo amputation—a life-altering outcome that researchers are urgently working to prevent.

Designed to address what researchers identify as a key underlying cause of chronic wounds—oxygen deficiency—the gel has shown promising results in animal studies.

According to Iman Noshadi, associate professor of bioengineering at UCR and leader of the research team, chronic wounds struggle to heal because they lack a stable and sufficient oxygen supply. Normal wound healing progresses through four stages: inflammation, formation of new blood vessels (vascularization), tissue remodeling, and regeneration.

Oxygen plays a critical role in each phase. When oxygen levels are inadequate, the wound becomes trapped in prolonged inflammation. "This condition allows bacteria to thrive and prevents healthy tissue repair," said the authors.

The condition known as hypoxia—where oxygen fails to reach deeper layers of damaged tissue—is especially problematic. Without oxygen penetrating the wound bed, healing mechanisms stall. To combat this, the UCR team created a soft, flexible gel capable of continuously generating oxygen directly at the injury site.

The gel is composed of water and a choline-based liquid that is antibacterial, non-toxic, and biocompatible. When connected to a small battery similar to those found in hearing aids, the system becomes a miniature electrochemical device. It splits water molecules to produce a slow, controlled stream of oxygen over an extended period, according to the study ‘A smart self-oxygenating system for localized and sustained oxygen delivery in bioengineered tissue constructs,’ published in Communications Materials, a journal from Nature Portfolio.

Unlike traditional wound dressings that either absorb fluids or release antimicrobial substances, this gel addresses the deeper problem of hypoxia. It molds precisely to the wound’s shape before setting, filling crevices where oxygen levels are lowest and infection risks are highest. This close contact ensures oxygen reaches areas that surface treatments often miss.

Another key advantage is sustained oxygen delivery. Since new blood vessel formation can take weeks, brief oxygen bursts are insufficient. The UCR system can maintain oxygen levels for up to a month, creating conditions that allow a chronic wound to behave more like a typical injury that heals naturally.

In experiments involving diabetic and older mice—chosen because their wounds resemble chronic wounds in elderly humans—untreated injuries failed to heal and frequently proved fatal. However, wounds treated with the oxygen-generating patch, replaced weekly, closed within approximately 23 days. The treated animals survived, demonstrating the gel’s significant potential.

Beyond wound healing, the technology may have broader implications. Oxygen and nutrient delivery are major obstacles in efforts to grow replacement tissues and organs—a key research focus in Noshadi’s laboratory.

As tissue thickness increases, it becomes difficult for oxygen to diffuse evenly, causing cell death. This oxygen-generating system could help sustain thicker engineered tissues, potentially advancing regenerative medicine and organ development.

The gel also provides an immune-regulating benefit. Chronic wounds often contain excessive reactive oxygen species—unstable molecules that damage cells and prolong inflammation. Choline, a component of the gel, helps calm this overactive immune response while stable oxygen supports regeneration. Instead of creating additional stress, the system restores balance to the wound environment.

While the gel cannot address all causes of chronic wounds—such as sedentary lifestyles, aging, and rising diabetes prevalence—researchers believe this innovation could reduce amputations, improve patient outcomes, and enhance quality of life.