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101.
Xiao-Gang Yang Ji-Rui Zhang Xu-Ke Tian Jian-Hua Qin Xin-Ya Zhang Lu-Fang Ma 《Angewandte Chemie (International ed. in English)》2023,62(7):e202216699
The development of efficient enzyme immobilization to promote their recyclability and activity is highly desirable. Zeolitic imidazolate framework-8 (ZIF-8) has been proved to be an effective platform for enzyme immobilization due to its easy preparation and biocompatibility. However, the intrinsic hydrophobic characteristic hinders its further development in this filed. Herein, a facile synthesis approach was developed to immobilize pepsin (PEP) on the ZIF-8 carrier by using Ni2+ ions as anchor (ZIF-8@PEP-Ni). By contrast, the direct coating of PEP on the surface of ZIF-8 (ZIF-8@PEP) generated significant conformational changes. Electrochemical oxygen evolution reaction (OER) was employed to study the catalytic activity of immobilized PEP. The ZIF-8@PEP-Ni composite attains remarkable OER performance with an ultralow overpotential of only 127 mV at 10 mA cm−2, which is much lower than the 690 and 919 mV overpotential values of ZIF-8@PEP and PEP, respectively. 相似文献
102.
Jindou Tian Prof. Dr. Qihui Chen Prof. Dr. Feilong Jiang Prof. Dr. Daqiang Yuan Prof. Dr. Maochun Hong 《Angewandte Chemie (International ed. in English)》2023,62(7):e202215253
Developing practical storage technologies for acetylene (C2H2) is important but challenging because C2H2 is useful but explosive. Here, a novel metal–organic framework (MOF) ( FJI-H36 ) with adaptive channels was prepared. It can effectively capture C2H2 (159.9 cm3 cm−3) at 1 atm and 298 K, possessing a record-high storage density (561 g L−1) but a very low adsorption enthalpy (28 kJ mol−1) among all the reported MOFs. Structural analyses show that such excellent adsorption performance comes from the synergism of active sites, flexible framework, and matched pores; where the adsorbed-C2H2 can drive FJI-H36 to undergo induced-fit transformations step by step, including deformation/reconstruction of channels, contraction of pores, and transformation of active sites, finally leading to dense packing of C2H2. Moreover, FJI-H36 has excellent chemical stability and recyclability, and can be prepared on a large scale, enabling it as a practical adsorbent for C2H2. This will provide a useful strategy for developing practical and efficient adsorbents for C2H2 storage. 相似文献
103.
Yan-Jun Yu Chen Zou Wan-Shan Shen Xiaopeng Zheng Qi-Sheng Tian You-Jun Yu Chun-Hao Chen Baodan Zhao Prof. Zhao-Kui Wang Prof. Dawei Di Prof. Osman M. Bakr Prof. Liang-Sheng Liao 《Angewandte Chemie (International ed. in English)》2023,62(22):e202302005
Perovskite nanocrystals (PeNCs) deliver size- and composition-tunable luminescence of high efficiency and color purity in the visible range. However, attaining efficient electroluminescence (EL) in the near-infrared (NIR) region from PeNCs is challenging, limiting their potential applications. Here we demonstrate a highly efficient NIR light-emitting diode (LED) by doping ytterbium ions into a PeNCs host (Yb3+ : PeNCs), extending the EL wavelengths toward 1000 nm, which is achieved through a direct sensitization of Yb3+ ions by the PeNC host. Efficient quantum-cutting processes enable high photoluminescence quantum yields (PLQYs) of up to 126 % from the Yb3+ : PeNCs. Through halide-composition engineering and surface passivation to improve both PLQY and charge-transport balance, we demonstrate an efficient NIR LED with a peak external quantum efficiency of 7.7 % at a central wavelength of 990 nm, representing the most efficient perovskite-based LEDs with emission wavelengths beyond 850 nm. 相似文献
104.
Jianwu Tian Bowen Li Fu Zhang Zhuo Yao Wentao Song Yufu Tang Yuan Ping Bin Liu 《Angewandte Chemie (International ed. in English)》2023,62(46):e202307288
The phototoxicity of photosensitizers (PSs) pre and post photodynamic therapy (PDT), and the hypoxic tumor microenvironment are two major problems limiting the application of PDT. While activatable PSs can successfully address the PS phototoxicity pre PDT, and type I PS can generate reactive oxygen species (ROS) effectively in hypoxic environment, very limited approaches are available for addressing the phototoxicity post PDT. There is virtually no solution available to address all these issues using a single design. Herein, we propose a proof-of-concept on-demand switchable photosensitizer with quenched photosensitization pre and post PDT, which could be activated only in tumor hypoxic environment. Particularly, a hypoxia-normoxia cycling responsive type I PS TPFN-AzoCF3 was designed to demonstrate the concept, which was further formulated into TPFN-AzoCF3 nanoparticles (NPs) using DSPE-PEG-2000 as the encapsulation matrix. The NPs could be activated only in hypoxic tumors to generate type I ROS during PDT treatment, but remain non-toxic in normal tissues, pre or after PDT, thus minimizing side effects and improving the therapeutic effect. With promising results in in vitro and in vivo tumor treatment, this presented strategy will pave the way for the design of more on-demand switchable photosensitizers with minimized side effects in the future. 相似文献
105.
Tiantian Wu Hong Wang Run Tian Shuang Guo Yuhui Liao Prof. Jianbing Liu Prof. Baoquan Ding 《Angewandte Chemie (International ed. in English)》2023,62(46):e202311698
Bacteria infection is a significant obstacle in the clinical treatment of exposed wounds facing widespread pathogens. Herein, we report a DNA origami-based bactericide for efficient anti-infection therapy of infected wounds in vivo. In our design, abundant DNAzymes (G4/hemin) can be precisely organized on the DNA origami for controllable generation of reactive oxygen species (ROS) to break bacterial membranes. After the destruction of the membrane, broad-spectrum antibiotic levofloxacin (LEV, loaded in the DNA origami through interaction with DNA duplex) can be easily delivered into the bacteria for successful sterilization. With the incorporation of DNA aptamer targeting bacterial peptidoglycan, the DNA origami-based bactericide can achieve targeted and combined antibacterial therapy for efficiently promoting the healing of infected wounds. This tailored DNA origami-based nanoplatform provides a new strategy for the treatment of infectious diseases in vivo. 相似文献
106.
Dr. Ligang Wang Dr. Hui Su Zhuang Zhang Junjie Xin Hai Liu Dr. Xiaoge Wang Dr. Chenyu Yang Xiao Liang Dr. Shunwu Wang Dr. Huan Liu Yanfei Yin Taiyan Zhang Prof. Yang Tian Dr. Yaping Li Prof. Qinghua Liu Prof. Xiaoming Sun Prof. Junliang Sun Prof. Dingsheng Wang Prof. Yadong Li 《Angewandte Chemie (International ed. in English)》2023,62(49):e202314185
Developing cost-effective and sustainable acidic water oxidation catalysts requires significant advances in material design and in-depth mechanism understanding for proton exchange membrane water electrolysis. Herein, we developed a single atom regulatory strategy to construct Co−Co dinuclear active sites (DASs) catalysts that atomically dispersed zirconium doped Co9S8/Co3O4 heterostructure. The X-ray absorption fine structure elucidated the incorporation of Zr greatly facilitated the generation of Co−Co DASs layer with stretching of cobalt oxygen bond and S−Co−O heterogeneous grain boundaries interfaces, engineering attractive activity of significantly reduced overpotential of 75 mV at 10 mA cm−2, a breakthrough of 500 mA cm−2 high current density, and water splitting stability of 500 hours in acid, making it one of the best-performing acid-stable OER non-noble metal materials. The optimized catalyst with interatomic Co−Co distance (ca. 2.80 Å) followed oxo-oxo coupling mechanism that involved obvious oxygen bridges on dinuclear Co sites (1,090 cm−1), confirmed by in situ SR-FTIR, XAFS and theoretical simulations. Furthermore, a major breakthrough of 120,000 mA g−1 high mass current density using the first reported noble metal-free cobalt anode catalyst of Co−Co DASs/ZCC in PEM-WE at 2.14 V was recorded. 相似文献
107.
Wei-Chen Zhu Yi-Fan Jiang Xin-Yu Liu Shi-Yin Tian Prof. Weidong Rao Prof. Shu-Su Shen Assoc. Prof. Ping Song Dr. Daopeng Sheng Prof. Shun-Yi Wang 《European journal of organic chemistry》2023,26(25):e202300379
A photoinduced synthesis of β-keto thiosulfone/β-keto selenosulfone by the reaction of α-bromoacetophenone with thiosulfonate/selenosulfonate under metal-free and visible light irradiation conditions is developed. Two C−S bonds or one C−S bond and one C−Se bond were constructed simultaneously. 相似文献
108.
Bingchu Tian Dr. Yanbo Shang Yi Tu Dr. Jun Hu Dr. Dong Han Qian Xu Prof. Shangfeng Yang Prof. Yifan Ye Dr. Honghe Ding Dr. Yu Li Prof. Junfa Zhu 《Chemphyschem》2023,24(20):e202300400
The interfacial electronic structure of perovskite layers and transport layers is critical for the performance and stability of perovskite solar cells (PSCs). The device performance of PSCs can generally be improved by adding a slight excess of lead iodide (PbI2) to the precursor solution. However, its underlying working mechanism is controversial. Here, we performed a comprehensive study of the electronic structures at the interface between CH3NH3PbI3 and C60 with and without the modification of PbI2 using in situ photoemission spectroscopy measurements. The correlation between the interfacial structures and the device performance was explored based on performance and stability tests. We found that there is an interfacial dipole reversal, and the downward band bending is larger at the CH3NH3PbI3/C60 interface with the modification of PbI2 as compared to that without PbI2. Therefore, PSCs with PbI2 modification exhibit faster charge carrier transport and slower carrier recombination. Nevertheless, the modification of PbI2 undermines the device stability due to aggravated iodide migration. Our findings provide a fundamental understanding of the CH3NH3PbI3/C60 interfacial structure from the perspective of the atomic layer and insight into the double-edged sword effect of PbI2 as an additive. 相似文献
109.
Mingqi Sun Jiaqi Meng Weier Bao Dr. Ming Liu Xiaojuan Li Zicheng Wang Zhecheng Ma Prof. Dr. Xuefei Wang Prof. Dr. Zhiyuan Tian 《Chemphyschem》2023,24(6):e202200716
Room temperature phosphorescence (RTP) materials are characterized with emission after removing the excitation source. Such long-lived emission feature possesses great potential in biological fluorescence imaging because it enables a way regarding temporal dimension for separating the interference of autofluorescence and common noises typically encountered in conventional fluorescence imaging. Herein, we constructed a new type of mesoporous silica nanoparticles (MSNs)-based composite nanoparticles (NPs) with dual-color long-lived emission, namely millisecond-level green phosphorescence and sub-millisecond-level delayed red fluorescence by encapsulating a typical RTP dye and Rhodamine dye in the cavities of the MSNs with the former acting as energy donor (D) while the latter as acceptor (A). Benefiting from the close D-A proximity, energy match between the donor and the acceptor and the optimized D/A ratio in the composite NPs, efficient triplet-to-singlet Förster resonance energy transfer (TS-FRET) in the NPs occurred upon exciting the donor, which enabled dual-color long-lived emission. The preliminary results of dual-color correlation imaging of live cells based on such emission feature unequivocally verified the unique ability of such NPs for distinguishing the false positive generated by common emitters with single-color emission feature. 相似文献
110.
Chang Liu Yunci Zhang Shanshan Tang Yi Wang Jing Tian Dongyu Gu Yi Yang 《Journal of separation science》2023,46(10):2200958
Robinia pseudoacacia flowers have attracted much attention because of numerous bioactivities. In this study, its extract showed the potential scavenging ability for 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) and 1,1-diphenyl-2-picrylhydrazyl free radicals. Under the guidance of antioxidant activity, the antioxidant extract was enriched by liquid-liquid extraction. The partition coefficients of the two main components in antioxidant extracts differed greatly, so in this study, elution-extrusion counter-current chromatography with the solvent system of n-hexane-ethyl acetate-methanol-water (2.5:5:2.5:5, v/v) was used to enhance the separation efficiency, and the two main components were successfully obtained. Among them, kaempferol showed strong antioxidant activity, which can be responsible for the activity of the extract. In order to deeply understand the antioxidant mechanism of kaempferol, the thermodynamics, frontier molecular orbital, and kinetics of scavenging free radicals were investigated by density functional theory. The results showed that 4′-OH in kaempferol was the most active group, which can scavenge free radicals by hydrogen atom transfer in non-polar solvents and activate 3-OH to generate double hydrogen atom transfer in the gas phase. But in polar solvents, it was more inclined to clear radicals through single electron transfer and proton transfer. The kinetic result showed that kaempferol needed 9.17 kcal/mol of activation energy to scavenge free radicals. 相似文献