Advances in the Rational Design, Mechanisms, and Applications of Lanthanide Nanoparticles for the Regulation of Reactive Oxygen Species.

Lanthanide nanoparticles provide an ideal platform for the precise regulation of reactive oxygen species (ROS) due to their reversible redox properties, photomagnetic characteristics, and functionalizable surfaces. This review summarizes recent advances in the mechanistic understanding, biomedical applications, and material design strategies of lanthanide nanoparticles for ROS modulation. Mechanistically, lanthanide nanoparticles generate ROS through photoexcited electron transfer, Fenton-like reactions, and ligand-mediated redox cycling, while also effectively scavenging ROS via reversible valence switching and metal-ligand synergistic effects. At the application level, these nanoparticles leverage their combined antioxidant and anti-inflammatory properties to provide protection against oxidative stress-related diseases, while enabling targeted tumor elimination through chemodynamic therapy, photodynamic therapy, sonodynamic therapy, radiosensitization, and multimodal imaging. Recent material design has encompassed upconversion architectures, multi-metal composite systems, single-atom catalysts, biodegradable systems, and artificial intelligence-assisted rational design. Despite remaining challenges in understanding metabolic pathways and achieving targeting precision, the integration of lanthanide nanomaterials with emerging therapeutic modalities and intelligent design strategies holds promise for innovative approaches to the diagnosis and treatment of ROS-associated diseases.