Differently sized NaGdF(4) nanocrystals with narrow particle size distributions were synthesized by a high temperature approach. Upon ligand exchange, the as-prepared hydrophobic NaGdF(4) nanocrystals were transferred into water by using asymmetric PEGs simultaneously bearing phosphate and maleimide groups. Further investigations demonstrated that the water-soluble NaGdF(4) nanocrystals, coated by PEG bearing two phosphate groups on the same side, exhibit not only excellent colloidal stability in water and PBS buffer, but also higher T1 relaxivity than Gd-DTPA (Magnevist). Through "click" reaction between the maleimide residue on particle surface and thiol group from the partly reduced anti-EGFR monoclonal antibody (mAb), NaGdF(4)-PEG-mAb nanoprobes were constructed, and their biocompatibility and binding specificity were evaluated through in vitro experiments. A series of in vivo experiments were then carried out for detecting intraperitoneal tumor xenografts in nude mice by using magnetic resonance (MR) imaging technique. The results revealed that the NaGdF(4)-PEG-mAb probes possessed satisfying tumor-specific targeting ability and strong MR contrast enhancement effects.

Cell-free DNA (cfDNA) released from damaged or dead cells can activate DNA sensors that exacerbate the pathogenesis of rheumatoid arthritis (RA). Here we show that ~40 nm cationic nanoparticles (cNP) can scavenge cfDNA derived from RA patients and inhibit the activation of primary synovial fluid monocytes and fibroblast-like synoviocytes. Using clinical scoring, micro-CT images, MRI, and histology, we show that intravenous injection of cNP into a CpG-induced mouse model or collagen-induced arthritis rat model can relieve RA symptoms including ankle and tissue swelling, and bone and cartilage damage. This culminates in the manifestation of partial mobility recovery of the treated rats in a rotational cage test. Mechanistic studies on intracellular trafficking and biodistribution of cNP, as well as measurement of cytokine expression in the joints and cfDNA levels in systemic circulation and inflamed joints also correlate with therapeutic outcomes. This work suggests a new direction of nanomedicine in treating inflammatory diseases.

The continuously growing demand for clean, sustainable power systems for consumer electronics, electric vehicles, and national grid storage is driving the research interest for electrochemical energy storage systems with better safety, lower cost, and higher energy density beyond current Li-ion battery. [1] Among alternative competitors, lithium sulfur (Li-S) battery has been considered as outstanding representative considering its high theoretical capacity (S: 1675 mAh g −1 and Li: 3860 mAh g −1), sustainability of S, and lowest reduction potential of Li (−3.04 V vs SHE). [2] Despite intensive efforts over decades, the Li-S battery still suffers from several detrimental issues associated with both cathode and anode. For S cathode, the diffusion of intermediates lithium polysulfides (LiPS) and sluggish S redox conversion kinetic cause unsatisfactory specific capacity, inferior rate performance, and rapid capacity degradation. [3] For Li anode, the uncontrollable dendrite growth and infinite volume expansion result in safety risk and low Coulombic efficiency (CE). [4] Therefore, it is highly urgent to design the kinetically advanced Li-S battery system with well-designed configuration for both LiPSsuppressed cathode and dendrite-free anode. Hollow carbon sphere nanoreactors with good electrical conductivity, large surface area, and enhanced structural stability have been widely applied as the host for secondary batteries to improve their electrochemical performance. [5] For example, as S cathode, a hollow porphyrin organic framework was designed for long cycling stability Li-S battery resulting from the physical confinement of LiPS. [6] Besides, double-shelled hollow carbon sphere was explored as a free-standing S host for highenergy-density Li-S battery. [7] As for Li anode, encapsulation of Li into the hollow carbon sphere was designed for high stable Li metal anode. [8] However, the shuttle effect and Li dendrite has not substantially been resolved because the physical effect only addresses the surface issue and not the root. To overcome this, integrating bare carbon nanostructures with catalysts, such as The lithium sulfur (Li-S) battery is a preferential option for next-generation energy storage technologies, but the lithium polysulfide shuttling, sluggish redox kinetics, and uncontrollable lithium dendrite growth hamper its commercial viability. Herein, well-dispersed single atom Zn-decorated hollow carbon spheres (Zn 1-HNC) are developed as dual-functional nanoreactors for polysulfides-suppressed sulfur cathodes (Zn 1-HNC-S) and dendrite-free lithium anodes (Zn 1-HNC-Li) simultaneously for high-capacity, high-rate, and long-cycling Li-S batteries with fast redox kinetics. Benefiting from its excellent electronic conductivity, high surface area (370 m 2 g −1), highly-effective active sites and protective carbon shell, the resultant nanoreactor possesses strong physical confinement, chemical anchoring, and exceptional electrocatalysis for polysulfides. Meanwhile, the nanoreactor with excellent lithiophilic ab...