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Artificial cells are synthetic constructs that emulate natural cells, with potential applications in areas of energy science, environmental treatment, and the study of life's origins. Nevertheless, the construction of artificial cells is a formidable undertaking, given the intricate nature of natural cells in structures, functions, and working mechanisms. With precise control, high automation, and excellent uniformity, microfluidics has emerged as a promising approach for the construction of artificial cells. This review summarizes the latest microfluidic techniques utilized to construct artificial cells, ranging from simple droplets to sophisticated cell‐inspired systems. These include the generation of droplets, the production of vesicles (lipid‐based and polymer‐based vesicles), the fabrication of polymeric microparticles with various compartments, shapes, and microstructures, as well as the manufacture of sophisticated cell‐inspired systems. The characteristics of different methods for the construction of artificial cells are discussed in detail. Furthermore, the wide‐ranging applications of artificial cells are also showcased. Finally, contemporary obstacles and forthcoming advancements are discussed in the field of microfluidic‐based artificial cells. This review is supposed to stimulate research in the construction of more functional and natural‐like artificial cells, as well as works in the fields of material, biology, environment, medicine, and energy. [ABSTRACT FROM AUTHOR]

The development of nanotechnology is becoming a major trend nowadays. Nanoparticles (NPs) have been widely used in fields including food, biomedicine, and cosmetics, endowing NPs more opportunities to enter the human body. It is well‐known that the gut microbiome plays a key role in human health, and the exposure of intestines to NPs is unavoidable. Accordingly, the toxicity of NPs has attracted more attention than before. This review mainly highlights recent advances in the evaluation of NPs' toxicity in the gastrointestinal system from the existing cell‐based experimental models, such as the original mono‐culture models, co‐culture models, three‐dimensional (3D) culture models, and the models established on microfluidic chips, to those in vivo experiments, such as mice models, Caenorhabditis elegans models, zebrafish models, human volunteers, as well as computer‐simulated toxicity models. Owing to these models, especially those more biomimetic models, the outcome of the toxicity of NPs acting in the gastrointestinal tract can get results closer to what happened inside the real human microenvironment. The toxicity of nanoparticles (NPs) has raised concerns recently because the exposure of intestines to NPs is unavoidable. Therefore, in this review, the recent evaluation models of NPs' toxicity in the gastrointestinal system have been highlighted, from mono‐culture, co‐culture, three‐dimensional (3D) culture, and the models established on microfluidic chips in vitro, to mice, Caenorhabditis elegans, zebrafish, and humans in vivo, as well as computer‐simulated toxicity models. In summary, the developments of these models facilitate the further applications of NPs. [ABSTRACT FROM AUTHOR]

Small‐molecule induction can lead to the oriented migration of metal elements, which affords functional materials with synergistic components. In this study, phosphating nickel foam (NF)‐supported octahedral WO3 with phosphine affords P‐WO3/NF electrocatalyst. Ni is found to form Ni−P bonds that migrate from NF to WO3 under the induction of P, resulting in the complex oxides W1.3Ni0.24O4 and Ni2P2O7 in the particle interior and nickel phosphide on the octahedral grain surface. The catalytic activity of P‐WO3/NF in the urea oxidation reaction (UOR) is improved by synergistic action of the components in the synthesized hybrid particles. A current density of 10 mA cm−2 can be reached at a potential of 1.305 V, the double layer capacitance of the catalyst is significantly increased, and the electron transfer impedance in catalytic UOR is reduced. This work demonstrates that small‐molecule induction is suitable for constructing co‐catalysts with complex components in a simple protocol, which provides a new route for the design of highly efficient urea oxidation electrocatalysts. [ABSTRACT FROM AUTHOR]

The manufacture of bionic materials to simulate the natural counterparts has attracted extensive attention. As one of the subcategories of biomimetic materials, the development of artificial enzyme is intensive pursuing. As a kind of artificial enzyme, nanozymes are dedicated to solve the limitations of natural enzymes. In recent years, attributed to the explosive development of nanotechnology, biotechnology, catalysis science, computational design and theory calculation, research on nanozymes has made great progress. To highlight these achievements and help researchers to understand the current investigation status of nanozyme, the state‐of‐the‐art development in nanozymes from fabrication materials to bioapplications are summarized. First different raw materials are summarized, including metal‐based, metal‐free, metal‐organic frameworks‐based, and some other novel matters, which are applied to fabricate nanozymes. The different types of enzymes‐like catalytic activities of nanozymes are briefly discussed. Subsequently, the wide applications of nanozymes such as anti‐oxidation, curing diseases, anti‐bacteria, biosensing, and bioimaging are discussed. Finally, the current challenges faced by nanozymes are outlined and the future directions for advancing nanozyme research are outlooked. The authors hope this review can inspire research in the fields of nanotechnology, chemistry, biology, materials science, and theoretical computing, and can contribute to the development of nanozymes. [ABSTRACT FROM AUTHOR]

Hydrogels are 3D cross‐linked polymer networks. Benefiting from the flexible designs and reasonable constructions of these networks, a large number of smart hydrogels with response characteristics to specific stimuli have received widespread attention and developed rapidly. The skeletal networks composed of the skeletal polymer chains and effectual cross‐links are the soul of such soft materials, and the response behaviors fundamentally depend on the dynamic characteristics of skeletal networks. Herein, the novel concepts of skeletal networks analysis to describe, understand, and guide the advanced designs and applications of smart hydrogels are proposed. Representative glucose‐sensitive hydrogels and DNA‐based smart hydrogels are reviewed to demonstrate the principle of skeletal networks analysis and clarify its practical guidance. Summarizing and classifying the characterizations and conversions of skeletal networks dynamics based on different response mechanisms provides a realistic solution. On this basis, advanced applications of smart hydrogels guided by skeletal networks dynamics including biochemical detection, cell mechanics sensing, drug delivery systems, and dynamic complex soft materials are typically reviewed. The skeletal networks analysis for smart hydrogels is of great significance for understanding the microstructures of hydrogels and guiding the designs of soft materials and their smart applications in the fields of analytical science and advanced materials. [ABSTRACT FROM AUTHOR]

The development of high‐efficiency nanozymes is of great significance in the field of nanozymology, because this is one of the prerequisites for the sophisticated performance of nanozymes. Herein, the developed metal–ligand cross‐linking strategy engineers porous carbon nanorod supported ultra‐small iron carbide nanoparticles that possess excellent oxidase‐like and peroxidase‐like enzyme activities. The fabricated nanozyme can efficiently accelerate the oxidation of ascorbate (AA) to enhance cancer cells ablation efficacy. Due to the nanozyme having great surface atoms utilization ratio and large specific surface area, the AA can be rapidly and completely autoxidized within 20 min. Mechanism research demonstrates that the nanozyme's first activation of O2 to generate superoxide free radicals (O2•−) via the oxidase‐like pathway, then the O2•− directly oxidizes AA and produces hydrogen peroxide (H2O2). Simultaneously, the H2O2 transforms into the toxic hydroxyl radical through the peroxidase‐like pathway and induces tumor cell death. Further in vitro and in vivo assays show the significant enhancement of the anti‐tumor efficacy through AA oxidation which is catalyzed by the developed nanozyme. It is expected that this work will benefit not only the development of other efficient nanozymes, but also future advances in the field of AA oxidation induced tumor therapy. [ABSTRACT FROM AUTHOR]

A novel armor‐type composite of metal–organic framework (MOF)‐encapsulated CoCu nanoparticles with a Fe3O4 core (Fe3O4@SiO2‐NH2‐CoCu@UiO‐66) has been designed and synthesized by the half‐way injection method, which successfully serves as an efficient and recyclable catalyst for the selective transfer hydrogenation. In this half‐way injection approach, the pre‐synthetic Fe3O4@SiO2‐NH2‐CoCu was injected into the UiO‐66 precursor solution halfway through the MOF budding period. The formed MOF armor could play a role of providing significant additional catalytic sites besides CoCu nanoparticles, protecting CoCu nanoparticles, and improving the catalyst stability, thus facilitating the selective transfer hydrogenation of nitrobenzaldehydes into corresponding nitrobenzyl alcohols in high selectivity (99 %) and conversion (99 %) rather than nitro group reduction products. Notably, this method achieves the precise assembly of a MOF‐encapsulated composite, and the ingenious combination of MOF and nanoparticles exhibits excellent catalytic performance in the selective hydrogen transfer reaction, implementing a "1+1>2" strategy in catalysis. [ABSTRACT FROM AUTHOR]

Hydrogenation of nitriles is an efficient and environmentally friendly route to synthesize symmetrical secondary amines, but it usually produces a mixture of amines, imines, and hydrogenolysis by‐products. Herein we report a magnetic quaternary‐component Pt−CuFe/Fe3O4 nanocatalyst system for the selective synthesis of symmetrical secondary amines with ammonia borane as hydrogen donor. The catalyst with a low Pt loading (0.456 wt%) is the source of the activity, and the d‐band electron transfer from Cu to Fe enhances the selectivity. This synergistic effect results in the transformation of benzonitrile to dibenzylamine with excellent conversion (up to 99 %) and nearly quantitative selectivity (up to 96 %) under mild reaction conditions, nevertheless, the reaction TOF is as high as up to 1409.9 h−1. A variety of nitriles are suitable for the synthesis of symmetrical secondary amines. More importantly, unwanted hydrogenolysis byproducts, especially toluene, is not detected at all. In addition, the catalyst is magnetically recoverable, and it can be reused up to five times. [ABSTRACT FROM AUTHOR]

Developing efficient, sustainable, and stable nanocatalysts continue being the struggling goal both for academia and for industrial. Carbocatalysts have attracted great attention due to high mass transfer ability, environmental sustainability and stability. Fabricating well‐defined carbonaceous nanocatalysts for heterogeneous catalysis is intensively pursuing. In this work, a newly developed economic and facile method was applied for the large‐scale fabrication of graphite sheet encapsulated magnetic carbocatalysts. The carbocatalysts was constructed via in‐situ pyrolysis of melamine‐metallo‐supramolecular polymer precursors (MMSP) under vacuum condition. The framework of MMSP was synthesized through the condensation reaction. As a proof‐of‐concept, this method was successfully applied for the fabrication of three kinds of graphite encapsulated magnetic carbocatalysts. Based on systematically optimization, the Pt−NiO‐1000@NC‐650 nanocatalyst demonstrated highly efficient and remarkable stability for the catalytic transfer hydrogenation of 4‐nitrophenol to produce corresponding 4‐aminophenol. The kinetics study of this catalytic system illustrates the reaction order is 1st for Pt−NiO‐1000@NC‐650. Furthermore, the kinetic constant (Kapp) is 1.57 min−1 and the turnover frequency (TOF) is up to 4, 268 h−1. [ABSTRACT FROM AUTHOR]

Effectively preventing graphene stacking and maintaining ultrathin layers remains a significant research effort for graphene preparation and applications. In this paper, a novel synthetic strategy based on catalyst migration on the surface of a salt template to control the growth of graphene is used to prepare 3D edge‐curled graphene (3D ECG). Under the synergistic effect of the steric hindrance and the migration of the Ni catalyst, 3D ECG forms a special structure in which the intermediate portion is flat and the edge is curled. The resultant unique structure not only effectively prevents the close stacking and aggregation of graphene, but also significantly improves its lithium storage performance. As an anode for lithium ion batteries, the reversible specific capacity can reach 907.5 and 347.8 mAh g−1 at the current density of 0.05 and 5.0 A g−1. Even after 1000 cycles, the specific capacity of 3D ECG can still be maintained at 605.2 mAh g−1 at a current density of 0.5 A g−1, demonstrating excellent rate performance and cycle performance. This new synthesis strategy and unique edge‐curled structure can be used to guide more design of 3D graphene materials for further functional applications. [ABSTRACT FROM AUTHOR]

Modifying the surface of metal catalyst is a crucial subject for improving the heterogeneous metal catalysts. It is still a great challenge to understand the structure‐activity relationship (SAR) between the surface supporting groups and the metal particles. Herein, Rh NPs supported on the magnetic silica sphere with various functional groups (−NH2, −SH, −SO3H, −N=CH2, −Cl, −NHCOCH3 and −NHCH2Ph) have been prepared for catalytic hydrogenation of nitroarenes under atmospheric pressure at room temperature. We discover that the chemical state of Rh NPs depends on the supporting groups significantly. The electron‐donating functionalities can effectively elevate the Rh0/Rh3+ ratio, which increase the catalytic performance both in conversion and selectivity. The amino group decorated catalyst has such a good selectivity that no dechlorination reaction is observable in the hydrogenation of 2‐chloro‐3‐nitropyridine. What's more, by introducing magnetic Fe3O4 nuclei and mesoporous silica encapsulating layer, the catalyst can be recovered conveniently by an external magnet, and can be reused 10 cycles without any loss of activity. [ABSTRACT FROM AUTHOR]

Various precious metal catalysts have been commonly used in catalytic reactions, but the differences and likeness between their catalytic performances are rarely systematically studied. Therefore, we have prepared the Pd, Pt, Rh, Ru, Au, and Ag/Fe3O4 catalysts, and the similarities and differences of various catalysts are analyzed by XRD, FT‐IR, TEM, HR‐TEM, XPS, BET, and VSM characterizations. Besides that platinum is the best catalyst component, the Pd and Rh/Fe3O4 catalysts also exhibit excellent catalytic activity and chemoselectivity, but the Ru, Au, Ag‐containing catalysts show poor catalytic performance for hydrogenation of 4‐nitrophenol. According to the kinetic study, we have demonstrated that the reaction orders for Pd, Pt, and Rh are 0.8, 0.8, and 1.5, respectively. This result reveals that the activity of Pd, Pt, and Rh‐containing catalysts can be precisely predicted. Moreover, our catalytic system is fascinating with many advantages such as environmental friendliness, mild reaction conditions, and the magnetic separability. [ABSTRACT FROM AUTHOR]

Control of chemoselectivity is a special challenge for the reduction of nitroarenes bearing one or more unsaturated groups. Here, we report a flower‐like Rh/α‐FeOOH catalyst for the chemoselective hydrogenation of nitrostyrene to vinylaniline over full conversion, which benefits the new functionalized aminostyrene because the multisubstituted aminostyrenes are usually commercially unavailable. This catalyst does not only show desirable selectivity for the vinylanilines, but also exhibits the inertness to various other reducible groups over wide reaction duration. The catalytic selectivity for the reduction of the nitro group towards vinyl group was investigated by the control experiments and FT‐IR analysis. We have found that the abundant hydroxyl groups in the α‐FeOOH may contribute to the improvement of catalytic activity and selectivity. Furthermore, the catalyst exhibits excellent stability and keeps its catalytic performance even after 6 cycles. [ABSTRACT FROM AUTHOR]

Facile and large‐scale preparation of materials with uniform distributions of ultrafine particles for catalysis is a challenging task, and it is even more difficult to obtain catalysts that excel in both the hydrogen evolution reaction (HER) and hydrogenation, which are the corresponding merging and splitting procedures of hydrogen, respectively. Herein, the fabrication of ultrafine bimetallic PtNi nanoparticles embedded in carbon nanosheets (CNS) by means of in situ self‐polymerization and annealing is reported. This bifunctional catalyst shows excellent performance in the hydrogen evolution reaction (HER) and the hydrogenation of p‐nitrophenol. Remarkably PtNi bimetallic catalyst with low metal loading (PtNi2@CNS‐600, 0.074 wt % Pt) exhibited outstanding HER activity with an overpotential as low as 68 mV at a current density of 10 mA cm−2 with a platinum loading of only 0.612 μgPt cm−2 and Tafel slope of 35.27 mV dec−1 in a 0.5 m aqueous solution of H2SO4, which is comparable to that of the 20 % Pt/C catalyst (31 mV dec−1). Moreover, it also shows superior long‐term electrochemical durability for at least 30 h with negligible degradation compared with 20 % Pt/C. In addition, the material with increased loading (mPtNi2@CNS‐600, 2.88 % Pt) showed robust catalytic activity for hydrogenation of p‐nitrophenol at ambient pressure and temperature. The catalytic activity towards hydrogen splitting is a circumstantial evidence that agrees with the Volmer–Tafel reaction path in the HER. [ABSTRACT FROM AUTHOR]

Abstract: A novel core–shell structured nanocatalyst (Fe3O4@SiO2‐NH2‐FeCu nanoparticles) with ultrafine FeCu alloy NPs magnetically immobilized in porous silica has been fabricated. The obtained catalyst revealed excellent activity and chemoselectivity for catalyzing the hydrogenation of nitroarenes to corresponding anilines using hydrazine hydrate as the hydrogen source, and the reaction could be carried out smoothly in water, which is an environmentally friendly solvent. The FeCu alloy effectively prevented the dehalogenation of halonitroarenes, and X‐ray photoelectron spectroscopy (XPS) study showed that it resulted from the electron‐enrichment of Fe from Cu. A kinetics study indicated that the reaction order was about 1.5 towards 4‐CNB and the apparent active energy (Ea) was 48.1 kJ mol−1, which is a relatively low value. Furthermore, the FeCu NPs are magnetically immobilized in the silica spheres (Fe3O4@SiO2), therefore the catalyst can be easily recovered by use of an external magnet and also possesses a long life time. [ABSTRACT FROM AUTHOR]

Abstract: Smart hydrogels with responsive behaviors have attracted tremendous attention. However, it is still a challenge to synthesize stretchable hydrogels capable of changing their original properties in response to multiple external stimuli. Here, integration of actuation function, shape memory, and self‐healing capability in a highly stretchable hydrogel under triple external triggers is achieved by rationally engineering multiple functional moieties. The hydrogel exhibits high stretchability (average relative strain (mm/mm) is >15) and excellent fatigue resistance during 100 loading cycles of 100% strain. Incorporating a moisture‐insensitive polymer film with the hydrogel, hydroactuated functionality is demonstrated. Moreover, shape memory and self‐healing abilities of the hydrogel are realized by the formation of ionic crosslinking or dynamic borate ester in conditions of multivalent cations and pH, respectively. Deformable plastic flowers are displayed in this work as a proof‐of‐concept, and it is believed that this smart hydrogel could be used in plenty of frontier fields, such as designing electronic devices, soft robotics, and actuators. [ABSTRACT FROM AUTHOR]

Abstract: A novel asymmetrical cyanine dye (TR) with NIR absorption at 970 nm was synthesized and applied in photoacoustic imaging (PAI) in vivo for the first time. The advantages of asymmetrical structure in PAI was demonstrated with DFT calculation and verified by related experiments. BSA was selected as the matrix to encapsulate TR‐BSA nanoparticles (TR‐NPs) which was investigated as a PAI agent. Exceptional performance of TR‐NPs was shown in Balb/c rats caudal vein model; the details could be clearly displayed and identified at a 0.1 mm scale. [ABSTRACT FROM AUTHOR]

We present a novel strategy for the scalable fabrication of γ-Fe2O3@3DPCF, a three-dimensional porous carbon framework (PCF) anchored ultra-uniform and ultra-stable γ-Fe2O3 nanocatalyst. The γ-Fe2O3@3DPCF nanocomposites were facilely prepared with the following route: condensation of iron(III) acetylacetonate with acetylacetonate at room temperature to form the polymer precursor (PPr), which was carbonized subsequently at 800 °C. The homogeneous aldol condensation offered an ultra-uniform distribution of iron, so that the γ-Fe2O3 nanoparticles (NPs) were uniformly distributed in the 3D carbon architecture with the average size of approximate 20 nm. The Fe2O3 NPs were capped with carbon, so that the iron oxide maintained its γ-phase instead of the more stable α-phase. The nanocomposite was an excellent catalyst for the reduction of nitroarene; it gave >99 % conversion and 100 % selectivity for the reduction of nitroarenes to the corresponding anilines at 100 °C. The fabrication of the γ-Fe2O3@3DPCF nanocatalyst represents a green and scalable method for the synthesis of novel carbon-based metal oxide nanostructures. [ABSTRACT FROM AUTHOR]

A magnetically separable core-shell-shell nanosphere, Fe3O4@nSiO2-SO3H@MS-NHCOCH3 (n=nonporous, MS=microporous SiO2), was fabricated as an acid-base collaborative catalyst for the three-component cyclization of aromatic aldehydes, nitroalkane, and sodium azide to afford 1 H-1,2,3-triazoles. The bifunctional heterogeneous catalyst showed high activity for this transformation and good chemoselectivity, and toxic HN3 was not released during the course of the reaction. A variety of aldehydes were transformed into the corresponding 5-aryl-1 H-1,2,3-triazoles in up to 98 % yield. Furthermore, the catalyst could be recovered by using an external magnetic field and reused many times without any loss in activity. In contrast, a homogeneous catalyst system comprising ammonium acetate/acetic acid also worked in this three-component cyclization to afford 1 H-1,2,3-triazoles. [ABSTRACT FROM AUTHOR]

Background Fuzhuan brick tea is a kind of microbial fermented tea, which has received increasing attention in recent years owing to its benefits for human health. In this study, the anti-obesity and hypolipidemic effects of Fuzhuan brick tea water extracts ( FTEs) were investigated. Results FTEs consisted of 204.07 ± 3.38 mg g−1 polyphenol, 109.20 ± 1.36 mg g−1 flavonoids, and others. The FTEs significantly suppressed the increase of body weight and accumulation of adipose tissue, and reduced the level of serum triacylglycerol, total cholesterol and low-density lipoprotein ( LDL) cholesterol in obese rats fed a high-fat diet. Moreover, FTEs attenuated the gene expression of sterol regulatory element binding protein-1c, fatty acid synthase and CCAAT/enhancer binding protein α, which is related to lipogenic metabolism. In contrast, the gene expressions of enzymes involved in energy expenditure and lipodieresis including hepatic peroxisome proliferator-activated receptor α, carnitine palmitoyltransferase 1a and LDL receptor gene expression were increased by FTE treatment. Conclusions Our study demonstrates that FTEs have anti-obesity and hypolipidemic functions, suggesting that it might be effective for treatment of obesity and hyperlipemia. [ABSTRACT FROM AUTHOR]

Nutritional intervention is effective in reducing the risk of neural tube defects (NTDs). To determine the effects of nutritional supplementation on human metabolism, a metabonomic study was carried out on 96 women of reproductive age. Subjects with nutritional intervention were given fortified wheat flour (containing folic acid, vitamin B, vitamin B, ferric sodium edetate and zinc oxide) for 8 months. Serum metabolic fingerprinting was detected via ultraperformance liquid chromatography in tandem with time-of-flight mass spectrometry (UPLC-TOF MS), and data acquired was processed by multivariate statistical analysis. The result revealed a significant difference between the control and intervention group. Twenty potential biomarkers, including fructose 6-phosphate, sphingosine 1-phosphate, docosahexaenoic acid and hexadecanoic acid, were located and identified by the accurate mass measurement of TOF MS. These compounds are believed to be functionally related to anti-oxidative competence in vivo. In conclusion, metabonomics study is a valuable approach in exploring the effect mechanism of nutritional intervention on NTD prevention. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]