In-situ growth of CeO2 on biofilms: Innovative nanoparticles for photothermal therapy & multi-pronged attack on Alzheimer's disease.

Alzheimer's disease (AD) is complex and multifactorial, and its pathogenesis involves multiple factors and processes. This study pioneered the in situ growth of cerium oxide nanoparticles on macrophage membranes (Ce-RAW). Further, carbon quantum dots (CQD) were biomimetically modified by Ce-RAW, leading to the synthesis of a multifunctional nanocomposite (CQD-Ce-RAW). Within the framework of this research, CQD-Ce-RAW was strategically combined with photothermal therapy (PTT), aiming to achieve a more significant therapeutic effect. The macrophage membrane confers the system with anti-phagocytic and anti-inflammatory biological functions. More importantly, the ultra-small size of cerium oxide grown on the membrane acts as a reactive oxygen species (ROS) scavenger and alleviates the degree of oxidative stress. Meanwhile, CQD as a photosensitizer helps dissociate amyloid-β (Aβ) aggregates and chelates excess copper ions, thus further inhibiting Aβ aggregation. Cell experiments showed that CQD-Ce-RAW combined with PTT could effectively degrade and inhibit the aggregation of Aβ, remove ROS, and improve cell survival rate. The results of in vivo photothermal experiments demonstrated that near-infrared light enhanced the efficiency of drug penetration through the blood-brain barrier and facilitated its accumulation in brain tissue. This comprehensive therapeutic approach can intervene in the disease progression from multiple pathways, providing a new prospect for treating AD.