Search

Background: Superparamagnetic iron core iron oxide shell nanocubes have previously shown superior performance in magnetic resonance imaging T2 contrast enhancement compared with spherical nanoparticles. Methods: Iron core iron oxide shell nanocubes were synthesized, stabilized with dimercaptosuccinic acid (DMSA-NC) and physicochemically characterized. MRI contrast enhancement and biocompatibility were assessed in vitro. Results: DMSA-NC showed a transverse relaxivity of 122.59 mM-1·s-1 Fe. Treatment with DMSA-NC did not induce cytotoxicity or oxidative stress in U-251 cells, and electron microscopy demonstrated DMSA-NC localization within endosomes and lysosomes in cells following internalization. Global proteomics revealed dysregulation of iron storage, transport, transcription and mRNA processing proteins. Conclusion: DMSA-NC is a promising T2 MRI contrast agent which, in this preliminary investigation, demonstrates favorable biocompatibility with an astrocyte cell model. MRI is a powerful tool used in the diagnosis of cancer, strokes and other injuries. An MRI scan can be improved with the use of iron oxide nanoparticles, which enhance the contrast of the image. In this study we have developed cube-shaped iron nanoparticles (nanocubes), which have been previously shown to be more effective at inducing contrast. We demonstrated that iron-based nanocubes do not damage or induce stress in cells and work effectively as an MRI contrast agent. We further analyzed how the nanocubes may affect cell functioning by investigating changes to protein levels in the cells. The results of this study are promising steps towards using iron-based nanocubes as a tool to improve the clarity of MRI scans for medical imaging and diagnosis. Future work must determine whether these nanocubes work effectively and safely in an animal model, which is a critical step in progressing to their use in clinical settings. [ABSTRACT FROM AUTHOR]

With freshwater resources becoming increasingly scarce, the photocatalytic seawater splitting for hydrogen production has garnered widespread attention. In this study, a novel photocatalyst consisting of a Cu core coated is introduced with N-doped C and decorated with single Co atoms (Co-NC@Cu) for solar to hydrogen production from seawater. This catalyst, without using noble metals or sacrificial agents, demonstrates superior hydrogen production effficiency of 9080 µmolg -1 h -1 , i.e., 4.78% solar-to-hydrogen conversion efficiency, and exceptional long-term stability, operating over 340 h continuously. The superior performance is attributed to several key factors. First, the focus-light induced photothermal effect enhances redox reaction capabilities, while the salt-ions enabled charge polarization around catalyst surfaces extends charge carrier lifetime. Furthermore, the Co─NC@Cu exhibits excellent broad light absorption, promoting photoexcited charge production. Theoretical calculations reveal that Co─NC acts as the active site, showing low energy barriers for reduction reactions. Additionally, the formation of a strong surface electric field from the localized surface plasmon resonance (LSPR) of Cu nanoparticles further reduces energy barriers for redox reactions, improving seawater splitting activity. This work provides valuable insights into intergrating the reaction environment, broad solar absorption, LSPR, and active single atoms into a core-shell photocatalyst design for efficient and robust solar-driven seawater splitting., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)