CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Xiaopeng Zhang,Yulong Li,Rui Zhang,Ying Chen,Gaofeng Zhao,Weizhen Zhao,Xia-Chao Chen,Suojiang Zhang
Polyelectrolyte multilayers have received broad interests in the fields of functional coatings due to their easy deposition procedure, environmentally friendly nature and wide sensitivities to manifold external stimuli. Stimuli-triggered generation of nanoscopic structures on polyelectrolyte multilayers can be reversible generally when their structural size is less than dozens of nanometers. Transforming larger structures reversibly would represent a breakthrough of these materials for novel applications. Herein, we report that surface structures up to hundreds of nanometers can be developed on exponentially growing polyelectrolyte multilayers reversibly, which feature the diffusion of polyelectrolytes throughout the whole assemblies. These multilayers are prepared utilizing pH-amplified layer-by-layer assembly of branched polyethylenimine and photo-reactive poly(acrylic acid) azido derivative. Other than applying a single stimulus on the mobility of polymeric chains, the surface structures were developed by inducing electrostatic repulsion between chains in aqueous phases while subsequently erased by shielding supramolecular electrostatic interactions in gaseous phases. These processes are completely reversible and one potential application of this dynamic platform is to be a “smart” material for reversible visualization of various high-definition patterns with fine brightness contrast, which can be especially significant in some cutting-edge fields like the Internet of Things, information encryption/decryption and anti-counterfeiting. Beyond that, such dynamic platform can be very useful in many other research fields, such as surface wettability and smart homes.
研究领域:
材料科学
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纳米技术
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表面化学
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DOI
高影响因子
Journal of Materials Chemistry B
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2023
·Vol. 11
·期 29
·6943-6951
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IF 7
Lanheng Nie,Zhengyu Tao,Xueying Zhu,Xin Huang,Xiaoman Liu
In recent years, developing artificial cells of higher complexity has emerged as being key to simulating advanced life behaviors, among which coacervate microdroplets are a promising kind of model artificial cell. Constructing simple coacervate systems in vitro which can subsequently achieve specific responses to environmental stimuli to form coacervate microdroplet communities are fundamental for studying the interactions between liquid–liquid phase separated molecules and the way such interactions determine material properties, composition and phase behavior. Herein, we propose a membrane-free artificial cell based on recombinant spidroin, NT2RepCT, which utilizes the complex structure of spidroin to provide coacervate microdroplets with a unique population morphology in response to environmental stimuli. By changing the environmental conditions such as protein concentration, pH and temperature, the coacervate microdroplets of single-type, regular adhesion-type and irregular adhesion-type were statistically generalized, and it is highlighted that the adhesion-type of coacervate microdroplets depended on the α-helical percentage, complex folding degree of spidroin and internally hydrophobic environment of the coacervate, while it was inversely proportional to the surface hydrophobic environment. Much more interesting, regulation of the non-enzymatic polymerization reaction of oligonucleotides was successfully achieved by adjusting the population morphology of coacervate microdroplets.
研究领域:
生物化学
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生物物理
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合成生物学
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2024
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IF 10.7
Yue Li,Mengting Chen,Yanjun Ding,Yanke Li,Mingming Guo,Yichuan Zhang
Pickering emulsions stabilized by solid particles are more stable and environmentally friendly compared to traditional surfactants. Herein, a series of Chitosan-g-Poly(N-vinylcaprolactam) (CS-g-PNVCL) microgel particles were synthesized via a free radical surfactant-free emulsion copolymerization and the obtained particles were used to stabilize Pickering emulsions. It is found that the ratio (CS/PNVCL = 60 wt%) was optimal to produce Pickering emulsions. The microstructures of Pickering emulsions can maintain for 60 days at room temperature and this long-term stability is attributed to the CS-g-PNVCL microgel particles adsorbed at the oil-water interface. The Pickering emulsions displayed thermo-responsive characteristics when exposed to environmental stimuli. The emulsions became destabilized with an increase in pH and temperature. The droplets turned unstable and irregular due to excessive NaCl concentration, caused by electrostatic repulsion between the microgel particles. This study presents a novel way to form smart and uniform Pickering emulsions with the application potential in food, cosmetics, and drug delivery, etc.
研究领域:
材料科学
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化学工程
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胶体与表面化学
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药学
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产品关联
DOI
PubMed
高影响因子
Journal of Macromolecular Science Part B-Physics
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2023
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IF 1.4
Xinyun Liu,Hua Lei,Jing Xiong
Intelligent or smart polymer materials are those which are either “active” or responsive to a variety of environmental stimuli, such as changes in pH, temperature, ionic strength or electric field, or the presence of a specific chemical substrate. A thermally sensitive polymer, poly(N-isopropylacrylamide) (PNIPAAm), has been of great interest because aqueous solutions of PNIPAAm undergo fast, reversible switching of hydrophilicity/hydrophobicity around 32 °C at their lower critical solution temperature (LCST) of about 29–38 °C (different with variations in their structure). PNIPAAm chains show an expanded conformation in water below the LCST because of strong hydration and change to the compact forms above the LCST by sudden dehydration; this is the reversible switching effect of hydrophilic to hydrophobic. These switchable materials may have wide applications in functional textiles, controllable drug release and special fibers. Electrospinning is a simple, convenient, and versatile technique for generating fibers with diameters that range from several micrometers to tens of nanometers. Herein, we report an electrospinning method to prepare nano PNIPAAm fiber and their thermal response was characterized. Based on the results, the diameters of the PNIPAAm nanofibers within the respective system were around 200 nm and beads-less; they were successfully prepared by an electrospinning method in all cases and the reversible switching with LCST (32 °C) feature was observed clearly in the fibers.
研究领域:
材料科学
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高分子科学
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纳米技术
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智能材料
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静电纺丝技术
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DOI
高影响因子
Nanoscale Advances
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2024
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IF 4.6
Jialing Hu,Fei Zhao,Huan Ling,Yunxiang Zhang,Qian Liu
Single-particle detection and sensing, powered by Förster Resonance Energy Transfer (FRET), offers precise monitoring of molecular interactions and environmental stimuli at a nanometric resolution. Despite its potential, the widespread use of FRET has been curtailed by the rapid photobleaching of traditional fluorophores. This study presents a robust single-particle FRET platform utilizing upconversion nanoparticles (UCNPs), which stand out for their remarkable photostability, making them superior to conventional organic donors for energy transfer-based assays. Our comprehensive research demonstrates the influence of UCNPs' size, architecture, and dye selection on the efficiency of FRET. We discovered that small particles (~14 nm) with a Yb3+-enriched outermost shell exhibit a significant boost in FRET efficiency, a benefit not observed in larger particles (~25 nm). 25 nm UCNPs with an inert NaLuF4 shell demonstrated a comparable level of emission enhancement via FRET as those with a Yb3+-enriched outermost shell. At the single-particle level, these FRET-enhanced UCNPs manifested an upconversion green emission intensity that was 8.3 times greater than their unmodified counterparts, while maintaining notable luminescence stability. Our upconversion FRET system opens up new possibilities for developing more effective high-brightness, high-sensitivity single-particle detection, and sensing modalities
研究领域:
纳米技术
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光学
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生物物理学
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材料科学
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分析化学
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生物传感
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产品关联
DOI
PubMed
高影响因子
Advanced Science
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2023
·Vol. 10
·期 11
·2300347
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IF 15.1
Yi Pan,Chang Li,Xiaoyu Hou,Zhenyu Yang,Mingzhu Li,Ho Cheung Shum
Stimuli-responsive structural coloration allows the color change of soft substrates in response to environmental stimuli such as heat, humidity, and solvents. Such color-changing systems enable smart soft devices, such as the camouflageable skin of soft robots or chromatic sensors in wearable devices. However, individually and independently programmable stimuli-responsive color pixels remain significant challenges among the existing color-changing soft materials and devices, which are crucial for dynamic display. Inspired by the dual-color concavities on butterfly wings, a morphable concavity array to pixelate the structural color of two-dimensional photonic crystal elastomer and achieve individually and independently addressable stimuli-responsive color pixels is designed. The morphable concavity can convert its surface between concave and flat upon changes in the solvent and temperature, accompanied by angle-dependent color-shifting. Through multichannel microfluidics, the color of each concavity can be controllably switched. Based on the system, the dynamic display by forming reversibly editable letters and patterns for anti-counterfeiting and encryption are demonstrated. It is believed that the strategy of pixelating optical properties through locally altering surface topography can inspire the design of new transformable optical devices, such as artificial compound eyes or crystalline lenses for biomimetic and robotic applications.
研究领域:
材料科学
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光学
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机器人学
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仿生学
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纳米技术
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软物质物理
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显示技术
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防伪技术
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密码学
✓ 已验证
产品关联
DOI
PubMed
高影响因子