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An integrated and simplified microfluidic device using a 250 [micro]m X 1-4 cm of organic light emitting diode (OLED) array as a two-dimensional light source for single-channel and multichannel whole-column imaging detection was developed. This fluorescence detection system was used for isoelectric focusing (IEF) of R-phycoerythrin in a microchip. The IEF conditions were optimized, and the total analysis time was extremely reduced to 30 s for 2-cm-long microchannels at 700 V/cm of electric field strength without the presence of electroosmotic flow. The compression of pH gradient caused by electrolytes drawing into the microchannels was efficiently restrained when 1% hydroxylpropylmethyl cellulose in 2% ampholyte was used as the carder for IEF. Under optimized IEF conditions, the detection limit of this system was ~0.6 [micro]g/mL or 45 pg at 75 nL/column injection of R-phycoerythrin. This OLED-induced fluorescence detection system for WCID provides a high-speed IEF technique with quantitative ability and the potential for high integration and throughput microchip systems.

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]

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]

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]

Currently, the design of carbon-based composite as a high-performance anode material for lithium-ion batteries (LIBs) presents challenges for commercial application. Herein, we developed a three-dimensional carbon-based material with a nanotube-sheet mutual support structure (MS-CNTS) engineered by the catalytic effect of Co species. The present work highlights a concise 'solvent-free' synthetic method allowing for large-scale output, which is potentially available for low cost commercial use. With the readily available acetylacetonate and cobalt (II) acetylacetonate as starting chemicals, this nanostructured carbonaceous material is fabricated with aldol condensation to construct a Co-contained carbon-link network polymer precursor followed by annealing under argon. It is composed of brim-curled graphene-like carbon nanosheets and carbon nanotubes, which support each other's structures to effectively avoid agglomeration. Therefore, it enables high performance in LIBs. In spite of the trace amount of cobalt, the carbon-based MS-CNTS anode delivers a high charge capacity of 1028 mAh g−1 at 0.1 A g−1, high rate capacity of 495 mAh g−1 at 2 A g−1, and ultra-long cycling life with a very low capacity decay of 0.008% per cycle over 1000 cycles at 0.5 A g−1, accompanied by 100% Coulombic efficiency. From full cell measurements, we further confirm the considerable promise of MS-CNTS as anodes with a long cycling life. [ABSTRACT FROM AUTHOR]