Ultrafast Fabrication of Iron/Manganese Co-Doped Bismuth Trimetallic Nanoparticles: A Thermally Aided Chemodynamic/Radio-Nanoplatform for Low-Dose Radioresistance

FePd Nanozyme- and SKN-Encapsulated Functional Lipid Nanoparticles for Cancer Nanotherapy via ROS-Boosting Necroptosis

Cell necroptosis has presented great potential, acting as an effective approach against tumor apoptotic resistance, and it could be further enhanced via accompanying reactive oxygen species (ROS) overexpression. However, whether overproduced ROS assists the necroptotic pathway remains unclear. Thus, iron-palladium nanozyme (FePd NZ)- and shikonin (SKN)-encapsulated functional lipid nanoparticles (FPS-LNPs) were designed to investigate the ROS overexpression-enhanced SKN-induced necroptosis. In this system, SKN acts as an effective necroptosis inducer for cancer cells, and FePd NZ, a sensitive Fenton reaction catalyst, produces extra-intracellular ROS to reinforce the necroptotic pathway. Both in vitro and in vivo antitumor evaluation revealed that FPS-LNPs presented the best tumor growth inhibition efficacy compared with FP-LNPs or SKN-LNPs alone. Meanwhile, induced necroptosis by FPS-LNPs can further trigger the release of damage-associated molecular patterns (DAMPs) and antigens from dying tumor cells to activate the innate immune response. Taking biosafety into consideration, this study has provided a potential nanoplatform for cancer nanotherapy via inducing necroptosis to avoid apoptosis resistance and activate CD8+ T cell immune response.

Therapeutic application of manganese-based nanosystems in cancer radiotherapy

Radiotherapy is an important therapeutic modality in the treatment of cancers. Nevertheless, the characteristics of the tumor microenvironment (TME), such as hypoxia and high glutathione (GSH), limit the efficacy of radiotherapy. Manganese-based (Mn-based) nanomaterials offer a promising prospect for sensitizing radiotherapy due to their good responsiveness to the TME. In this review, we focus on the mechanisms of radiosensitization of Mn-based nanosystems, including alleviating tumor hypoxia, increasing reactive oxygen species production, increasing GSH conversion, and promoting antitumor immunity. We further illustrate the applications of these mechanisms in cancer radiotherapy, including the development and delivery of radiosensitizers, as well as their combination with other therapeutic modalities. Finally, we summarize the application of Mn-based nanosystems as contrast agents in realizing precision therapy. Hopefully, the present review will provide new insights into the biological mechanisms of Mn-based nanosystems, as well as their applications in radiotherapy, in order to address the difficulties and challenges that remain in their clinical application in the future.

Metal selenide nanomaterials for biomedical applications

Metal selenide nanomaterials have received enormous attention as they possess diverse compositions, microstructures, and properties. The combination of selenium with various metallic elements gives the metal selenide nanomaterials distinctive optoelectronic and magnetic properties, such as strong near-infrared absorption, excellent imaging properties, good stability, and long in vivo circulation. This makes metal selenide nanomaterials advantageous and promising for biomedical applications. This paper summarizes the research progress in the last five years in the controlled synthesis of metal selenide nanomaterials in different dimensions and with different compositions and structures. Then we discuss how surface modification and functionalization strategies are well-suited for biomedical fields, including tumor therapy, biosensing, and antibacterial biological applications. The future trends and issues of metal selenide nanomaterials in the biomedical field are also discussed.

Shape-controllable and kinetically miscible Copper-Palladium bimetallic nanozymes with enhanced Fenton-like performance for biocatalysis

Bimetallic nanozymes have been emerging as essential catalysts due to their unique physicochemical properties from the monometallics. However, the access to optimize catalytic performance is often limited by the thermodynamic immiscibility and also heterogeneity. Thus, we present a one-step coreduction strategy to prepare the miscible Cu-Pd bimetallic nanozymes with controllable shape and homogeneously alloyed structure. The homogeneity is systematically explored and luckily, the homogeneous introduction of Cu successfully endows Cu-Pd bimetallic nanozymes with enhanced Fenton-like efficiency. Density functional theory (DFT) theoretical calculation reveals that Cu-Pd bimetallic nanozymes exhibit smaller d-band center compared with Pd nanozymes. Easier adsorption of H2O2 molecular contributed by the electronic structure of Cu significantly accelerate the catalytic process together with the strong repulsive interaction between H atom and Pd atom. In vitro cytotoxicity and intracellular ROS generation performance reveal the potential for in vivo biocatalysis. The strategy to construct kinetically miscible Cu-Pd bimetallic nanozymes will guide the development of bimetallic catalysts with excellent Fenton-like efficiency for biocatalytic nanomedicine.