Copper and copper oxide nanoparticles (NPs) are industrially important. In particular, Cu-based nanocatalysts find applicability in electrocatalysis and photocatalysis, profiting from the accessible oxidation states of copper and a band gap in the visible region of the Cu2O phase. However, in this case, the fast recombination of the charge carriers compromises the final photocatalytic efficiency.
The combination of Cu2O with metals often results in higher and more stable photocatalytic efficiency. Here, the fabrication of noble metal NPs [Au, Ag, Pd, and Pt] and Cu2O heterostructures (HSs) by a microwave (MW)-assisted synthesis is presented.The selectivity of the MW technique with a fast two-step protocol enabled us to easily prepare these multicomponent nanoparticles in a short time (∼40 min). First, metal NPs (Au, Ag, or Pd) are synthesized through a MW-assisted polyol approach, and these NPs serve as nucleation seeds for cubic Cu2O wrapping. Other types of heterostructures were found when using smaller Pt NPs instead. Focusing on Au NPs as the core, we analyzed the effect of the gold to copper molar ratio on the shape yield of the nanocubes, reported their optic and plasmonic properties, and demonstrated the reproducibility and scalability of the synthetic routes. Here, we are providing a pioneering example of MW heating as a non-conventional energy source for a general chemical approach to attain a family of complex metal/metal oxide heterostructures.
Bioactive materials for therapy and diagnosis
Copper Oxide Nanocubes Wrapping Metals by Microwave Synthesis
The anionic cobaltabis (dicarbollide) [3,3′-Co(1,2-C2B9H11)2]−, [o-COSAN]−, is the most studied icosahedral metallacarborane. The sodium salts of [o-COSAN]− could be an ideal candidate for the anti-cancer treatment Boron Neutron Capture Therapy (BNCT) as it possesses the ability to readily cross biological membranes thereby producing cell cycle arrest in cancer cells. BNCT is a cancer therapy based on the potential of 10B atoms to produce α particles that cross tissues in which the 10B is accumulated without damaging the surrounding healthy tissues, after being irradiated with low energy thermal neutrons.
The development of artificial vesicles into responsive architectures capable of sensing the biological environment and simultaneously signaling the presence of a specific target molecule is a key challenge in a range of biomedical applications from drug delivery to diagnostic tools. Herein, the rational design of biomimetic DNA-grafted quatsome (QS) nanovesicles capable of translating the binding of a target molecule to amphiphilic DNA probes into an optical output is presented.
There is evidence that Deep Brain Stimulation (DBS) produces health benefits in patients even before initiating stimulation. Furthermore, DBS electrode insertion in rat infralimbic cortex (ILC) provokes antidepressant-like effects before stimulation, due to local inflammation and astrogliosis. Consequently, a significant effect of implanting electrodes is suspected. External fields, similar in magnitude to the brain’s endogenous fields, induce electric dipoles in conducting materials, in turn influencing neural cell growth through wireless effects. To elucidate if such dipoles influence depressive-like behavior, without external stimulation, the comparative effect of conducting and insulated electrodes along with the glial response is studied in unstressed rats.
Bacterial cellulose (BC) is a biocompatible polysaccharide produced by bacteria currently used in packaging, cosmetics, or health care. A highly attractive feature of BC is the possibility of patterning the BC pellicle during its biosynthesis, a concept coined as bio-lithography.
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