A Nanozyme-Based Bandage with Single-Atom Catalysis for Brain Trauma.

Neurotrauma is one of the most serious traumatic injuries, which can induce an excessive amount of reactive oxygen and nitrogen species (RONS) around wound, triggering a series of biochemical responses and neuroinflammation. Traditional antioxidant-based bandage can effectively decrease infection via preventing oxidative stress, but its effectiveness is limited to a short period of time due to the rapid loss of electron-donating ability. Herein, we developed a nanozyme-based bandage using single-atom Pt/CeO2 with a persistent catalytic activity for non-invasive treatment of neurotrauma. Single-atom Pt induced the lattice expansion and preferred distribution on (111) facets of CeO2, enormously increasing the endogenous catalytic activity. Pt/CeO2 showed a 2-10 times higher scavenging activity against RONS as well as 3-10 times higher multi-enzyme activities than CeO2 clusters. The single-atom Pt/CeO2 retained the long-lasting catalytic activity for up to a month without obvious decay due to enhanced electron donation through the Mars-van Krevelen reaction. In vivo studies disclosed that the nanozyme-based bandage at the single-atom level can significantly improve the wound healing of neurotrauma and reduce neuroinflammation.