Oxygen-Delivering Gel for Chronic Wounds

University of California, Riverside, researchers have developed an oxygen-delivering gel capable of healing injuries that might otherwise progress to limb loss. The new gel, tested in animal models, targets what researchers believe is a root cause of many chronic wounds: a lack of oxygen in the deepest layers of the damaged tissue. Without sufficient oxygen, wounds languish in a prolonged state of inflammation, allowing bacteria to flourish and tissue to deteriorate rather than regenerate. When oxygen from the air or bloodstream cannot penetrate far enough into injured tissue the result is hypoxia, which derails normal healing.

The soft, flexible gel contains water as well as a choline-based liquid that is antibacterial, nontoxic, and biocompatible. When paired with a small battery similar to those used in hearing aids, the gel becomes a tiny electrochemical machine splitting water molecules to generate a slow, steady stream of oxygen. Moreover, the gel conforms to the unique shape of each wound, filling crevices where oxygen levels are often lowest and infection risk is highest. Before it sets, the material molds precisely to the contours of the damaged tissue. Equally important, the oxygen delivery is continuous. Vascularization can take weeks, so brief bursts of oxygen are not enough. The new system can provide sustained oxygen levels for up to a month, helping transform a nonhealing wound into one that behaves like a normal injury.

In tests on diabetic and older mice, chosen because their wounds closely resemble chronic wounds in older humans, untreated injuries failed to heal and were often fatal. With the oxygen-generating patch applied and replaced weekly, wounds closed in about 23 days, and the animals survived. The gel’s chemistry offers an added benefit. Choline, a key component, has properties that help modulate the immune system and calm excessive inflammation. Chronic wounds are often overwhelmed by reactive oxygen species, which are unstable molecules that damage cells and prolong inflammation. By increasing stable oxygen while helping rein in this immune overreaction, the gel restores balance rather than triggering further stress.