The interactions of nanoparticles with the soft surfaces of biological systems like cells play key roles in executing their biomedical functions and in toxicity. The discovery or design of new biomedical functions, or the prediction of the toxicological consequences of nanoparticles in vivo, first require knowledge of the interplay processes of the nanoparticles with the target cells. This article focusses on the cellular uptake, location and translocation, and any biological consequences, such as cytotoxicity, of the most widely studied and used nanoparticles, such as carbon-based nanoparticles, metallic nanoparticles, and quantum dots. The relevance of the size and shape, composition, charge, and surface chemistry of the nanoparticles in cells is considered. The intracellular uptake pathways of the nanoparticles and the cellular responses, with potential signaling pathways activated by nanoparticle interactions, are also discussed.

Long-distance entanglement distribution is essential for both foundational tests of quantum physics and scalable quantum networks. Owing to channel loss, however, the previously achieved distance was limited to ~100 kilometers. Here we demonstrate satellite-based distribution of entangled photon pairs to two locations separated by 1203 kilometers on Earth, through two satellite-to-ground downlinks with a summed length varying from 1600 to 2400 kilometers. We observed a survival of two-photon entanglement and a violation of Bell inequality by 2.37 ± 0.09 under strict Einstein locality conditions. The obtained effective link efficiency is orders of magnitude higher than that of the direct bidirectional transmission of the two photons through telecommunication fibers.

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Lanthanide (Ln 3+ ) doped Gd 2 O 3 nanoparticles (NPs) have been prepared via a thermal treatment of gadolinium carbonate precursor, which was obtained by simple hydrothermal treatment of Gd(NO 3 ) 3 solution in the presence of urea and glycerol. The size of the nanoparticles could be fine tuned from 270 to 10 nm by varying the amount of glycerol, which acted as a chelating agent to control the size of the nanoparticles. Calcination of the gadolinium carbonate nanoparticles at 500 C led to the formation of uniform Gd 2 O 3 nanoparticles without any obvious morphology change. By doping the lanthanide ions (Yb, Er/Tm) into the Gd 2 O 3 host matrix, these nanoparticles emitted strong upconversion (UC) fluorescence under 980 nm near infrared (NIR) excitation. Moreover, their emission colors could be tuned by simply changing either the co-dopant concentration or the dopant species. Water dispersibility was achieved by forming a silica layer on the surface of the Gd 2 O 3 nanoparticles. The possibility of using these silica-coated upconversion nanoparticles for optical imaging in vitro/in vivo has been demonstrated. It was also shown that these Gd 2 O 3 nanoparticles brightened the T 1 -weighted images and enhanced r 1 relaxivity of water protons, which suggested they act as T 1 contrast agents for magnetic resonance (MR) imaging. Thus, Gd 2 O 3 nanoparticles doped with Ln 3+ ions provide the dual modality of optical and magnetic resonance imaging.

Graphene nanomaterials have many diverse applications, but are considered to be emerging environmental pollutants. Thus, their potential environmental risks and biosafety are receiving increased attention. Bioaccumulation and toxicity evaluations in plants are essential for biosafety assessment. In this study, C-stable isotope labeling of the carbon skeleton of graphene oxide (GO) was applied to investigate the bioaccumulation and toxicity of GO in wheat. Bioaccumulation of GO was accurately quantified according to theC/C ratio. Wheat seedlings were exposed to C-labeled GO at 1.0 mg/mL in nutrient solution for 15 d.C-GO accumulated predominantly in the root with a content of 112 μg/g at day 15, hindered the development and growth of wheat plants, disrupted root structure and cellular ultrastructure, and promoted oxidative stress. The GO that accumulated in the root showed extremely limited translocation to the stem and leaves. During the experimental period, GO was excreted slowly from the root. GO inhibited the germination of wheat seeds at high concentrations (≥0.4 mg/mL). The mechanism of GO toxicity to wheat may be associated with oxidative stress induced by GO bioaccumulation, reflected by the changes of malondialdehyde concentration, catalase activity, and peroxidase activity. The results demonstrate that C labeling is a promising method to investigate environmental impacts and fates of carbon nanomaterials in biological systems.

Nanomaterial-biology interaction is the critical step in the fate of biomedical nanomedicines, influencing the consequent biological outcomes. Herein, we present two-dimensional carbonbased nanomaterials−graphdiyne oxide (GDYO) nanosheets that interact with an intracellular protein corona consisting of signal transducer and activator of transcription 3 (STAT3), inducing the reeducation of immunosuppressive macrophages. The interaction at the GDYO−STAT3 interface, driven by structure matching, hydrogen bonding, and salt bridges, simultaneously triggers the immune response in the tumor microenvironment, facilitating cancer immunotherapy. For the first time, our data reveal an interaction mechanism between the nanoparticle−protein interfaces inevitably formed inside the cells that determines the macrophage phenotype. Our results suggest that GDYO nanosheets could be applied for local immunomodulation due to their function and structural organization of the intracellular protein corona occurred inside macrophages.

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