Oxygen-Releasing Gel Heals Chronic Wounds & Reduces Amputation Risk | UC Riverside Research

Chronic wounds, those that resist healing for longer than a month, represent a growing challenge for an aging population and individuals with conditions like diabetes. Affecting an estimated 12 million people globally, with roughly 4.5 million cases in the United States, these injuries carry a significant risk of infection, tissue damage, and, in approximately one in five patients, ultimately lead to amputation.

Now, researchers at the University of California, Riverside (UCR) have developed a novel oxygen-delivering gel that shows promise in promoting healing in these stubborn wounds. The innovation, detailed in a recent publication in Nature Communications Materials, addresses a fundamental obstacle to wound repair: a lack of oxygen in the deepest layers of damaged tissue.

“Chronic wounds don’t heal by themselves,” explains Iman Noshadi, UCR associate professor of bioengineering and lead researcher on the project. “There are four stages to healing chronic wounds: inflammation, vascularization where tissue starts making blood vessels, remodeling, and regeneration or healing. In any of these stages, lack of a stable, consistent oxygen supply is a big problem.”

When oxygen cannot adequately penetrate injured tissue, a condition known as hypoxia develops. This disrupts the normal healing process, trapping the wound in a prolonged inflammatory state and creating an environment conducive to bacterial growth and tissue deterioration rather than regeneration.

How the Oxygen-Generating Gel Works

The gel itself is a soft, flexible material composed of water and a choline-based liquid, chosen for its antibacterial, nontoxic, and biocompatible properties. The key to its functionality lies in its ability to act as a miniature electrochemical device when connected to a small battery – similar in size to those used in hearing aids. This device splits water molecules, steadily releasing oxygen directly into the wound bed.

Unlike existing treatments that primarily deliver oxygen to the wound surface, this gel is designed to conform to the precise contours of the injury. Before solidifying, it fills gaps and uneven areas where oxygen levels are typically lowest and the risk of infection is highest. This targeted delivery is crucial, as the formation of new blood vessels, essential for sustained oxygen supply, can take weeks.

“Continuous oxygen delivery is critical,” explains Prince David Okoro, a doctoral candidate in bioengineering at UCR and co-author of the study. “Short bursts of oxygen are not enough to support lasting repair. This system can maintain oxygen flow for up to a month, helping a stalled wound resume a more typical healing pattern.”

Promising Results in Animal Models

To evaluate the effectiveness of the oxygen-generating gel, researchers conducted studies on diabetic and older mice, whose wounds closely mimic the characteristics of chronic wounds seen in human patients. In untreated animals, injuries consistently failed to heal and often proved fatal. However, when the oxygen-producing gel was applied and replaced weekly, wounds healed within approximately 23 days, and the animals survived.

The researchers envision a potential product where the gel patch would be periodically renewed to maintain optimal oxygen delivery. “We could make this patch as a product where the gel may need to be renewed periodically,” Okoro stated.

Beyond Oxygen: Addressing Inflammation and Immune Response

The benefits of the gel may extend beyond simply providing oxygen. Choline, a key component of the gel, is known to help regulate immune activity and reduce excessive inflammation. Chronic wounds often exhibit high levels of reactive oxygen species – unstable molecules that damage cells and prolong inflammation. By supplying a stable source of oxygen while simultaneously calming the overactive immune response, the gel aims to create a more favorable environment for tissue repair.

“There are bandages that absorb fluid, and some that release antimicrobial agents,” Okoro notes. “But none of them really address hypoxia, which is the fundamental problem. We’re tackling that directly.”

Potential Applications Beyond Wound Care

The potential applications of this technology extend beyond the treatment of chronic wounds. Oxygen and nutrient deficiencies pose significant challenges in the field of regenerative medicine, particularly in efforts to grow replacement tissues and organs – a long-term goal of the Noshadi laboratory.

“When the thickness of a tissue increases, it’s hard to diffuse that tissue with what it needs, so cells start dying,” Noshadi explains. “This project can be seen as a bridge to creating and sustaining larger organs for people in need of them.”

Addressing a Growing Public Health Concern

While the oxygen-generating gel represents a promising technological advancement, researchers acknowledge that addressing the rising rates of chronic wounds requires a multifaceted approach. Factors such as aging, diabetes, and lifestyle choices all contribute to the problem.

“Our sedentary lifestyles are causing our immune responses to decrease,” says Baishali Kanjilal, a UCR bioengineer and co-author of the study. “It’s hard to get to the societal roots of our problems. But this innovation represents a chance to reduce amputations, improve quality of life, and give the body what it needs to heal itself.”