Exposed chronic wounds are often covered with hypoxic tissue and are accompanied by necrosis, ongoing inflammation, and anaerobic infection. Since the oxygen in the atmosphere can only penetrate about 0.3 mm of tissue, and it is difficult for the oxygen circulating in the blood to reach the chronic wound through the damaged blood vessels, a solution for local oxygen delivery is urgently needed.

Recently, Prof. Zhang Zhongtao and Prof. Yao Hongwei from Beijing Friendship Hospital affiliated to Capital Medical University and Cheng Yuhao's team from Nanjing University School of Medicine and School of Life Sciences have studied a nanoparticle that can locally deliver dissolved oxygen to the wound site by adding lyophilized oxygen, thereby changing the traditional gel-type wound dressing (Fig. 1). A related research paper, Nano-oxygenated hydrogels for locally and permeably hypoxia relieving to heal chronic wounds, was published in the journal Biomaterials.