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In this paper, a simple, but effective method is reported to construct the core−shell gold nanorod@metal–organic frameworks (AuNR@MOFs) as a multifunctional theranostic platform by using functionalized AuNRs as seed crystal for the growth of porphyrinic MOFs on the surface of AuNR. Such a delicate tunable core−shell composite not only possesses the improved drug loading efficiency, near‐infrared light‐trigger drug release, and fluorescence imaging, but also can produce reactive oxygen species as well as photothermal activity to achieve combined cancer therapy. It is further demonstrated that the camptothecin loaded AuNR@MOFs show distinctively synergistic efficiency for damaging the cancer cell in vitro and inhibiting the tumor growth and metastasis in vivo. The development of this high‐performance incorporated nanostructure will provide more perspectives in the design of versatile nanomaterials for biomedical applications.

Magnetic microrobots can be actuated in fuel-free conditions and are envisioned for biomedical applications related to targeted delivery and therapy in a minimally invasive manner. However, mass fabrication of microrobots with precise propulsion performance and excellent therapeutic efficacy is still challenging, especially in a predictable and controllable manner. Herein, we propose a facile technique for mass production of magnetic microrobots with multiple functions using Spirulina (Sp.) as biotemplate. Core−shell-structured Pd@Au nanoparticles (NPs) were synthesized in Sp. cells by electroless deposition, working as photothermal conversion agents. Subsequently, the Fe 3 O 4 NPs were deposited onto the surface of the obtained (Pd@Au)@Sp. particles via a sol−gel process, enabling them to be magnetically actuated. Moreover, the anticancer drug doxorubicin (DOX) was loaded on the (Pd@Au)/Fe 3 O

A significant pathological signature of Alzheimer's disease (AD) is the deposition of amyloid-β (Aβ) plaques in the brain and the synaptic dysfunction and neurodegeneration associated with it. Compounds or drugs that inhibit Aβ fibrillation are thus desirable to develop novel therapeutic strategies against AD. Conventional strategies usually require an elaborate design of their molecular structures. Here we report the size-effect of gold nanoparticles (AuNPs) and nanoclusters (AuNCs) in the inhibition of protein amyloidosis. Using l-glutathione stabilized AuNPs with different sizes and AuNCs as examples, we show that large AuNPs accelerate Aβ fibrillation, whereas small AuNPs significantly suppress this process. More interestingly, AuNCs with smaller sizes can completely inhibit amyloidosis. Dynamic light scattering (DLS) experiments show that AuNCs can efficiently prevent Aβ peptides from aggregation to larger oligomers (e.g. micelles) and thus avoid nucleation to form fibrils. This is crucially important for developing novel AD therapies because oligomers are the main source of Aβ toxicity. This work presents a novel strategy to design anti-amyloidosis drugs, which also provides interesting insights to understand how biological nanostructures participate in vivo in Aβ fibrillation from a new perspective.

BACKGROUND: Salicylic acid (SA) is recognised as an endogenous signal, mediating in plant defense and against pathogens. It has been reported that SA treatment can reduce decay and extend storage life of various fruit, such as bananas, peaches and apples.

Developing highly efficient and stable non-precious metal-based electrocatalysts for alkaline hydrogen oxidation reaction (HOR) is essential for the commercialization of alkaline exchange membrane fuel cells but remains a big challenge. Here, a simple strategy for constructing the Ni/Ni 3 N heterostructure electrocatalyst with remarkable catalytic performance toward HOR under alkaline electrolyte is reported. Density functional theory calculations and experimental results reveal that the inter-regulated d-band center of interfacial Ni and Ni 3 N derived from electron transfer from Ni to Ni 3 N across the interface can lead to the weakened hydrogen binding energy of Ni and strengthened hydroxyl binding energy of Ni 3 N, which, together with the decreased formation energy of water species, contributes to the outstanding HOR performance.

Magnetic micro-/nanorobots have been regarded as a promising platform for targeted drug delivery, and tremendous strategies have been developed in recent years. However, realizing precise and efficient drug delivery in vivo still remains challenging, in which the versatile integration of good biocompatibility and reconfiguration is the main obstacle for micro-/nanorobots. Herein, we proposed a novel strategy of magnetic biohybrid microrobot multimers (BMMs) based on Chlorella (Ch.) and demonstrated their great potential for targeted drug delivery. The spherical Ch. cells around 3–5 μm were magnetized with Fe3O4 to fabricate biohybrid microrobots and then loaded with doxorubicin (DOX). Using magnetic dipolar interactions, the microrobot units could reconfigure into chain-like BMMs as tiny dimers, trimers, and so forth via attraction-induced self-assembly and disassemble reversibly via repulsion. The BMMs exhibited diverse swimming modes including rolling and tumbling with high maneuverability, and the rolling dimer’s velocity could reach 107.6 μm/s (∼18 body length/s) under a 70 Gs precessing magnetic field. Furthermore, the BMMs exhibited low cell toxicity, high DOX loading capacity, and pH-triggered drug release, which were verified by chemotherapy experiments toward HeLa cancer cells. Due to the remarkable versatility and facile fabrication, the BMMs demonstrate great potential for targeted anticancer therapy.

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