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181.
《Journal of Saudi Chemical Society》2023,27(5):101708
Praseodymium oxide (Pr6O11), hematite (Fe2O3), graphene oxide (GO), and polycaprolactone (PCL) based polymeric nanocomposites (NCs) are fabricated, aiming their usage as bio-scaffold for medical purposes. Because of their distinctive light absorption and stability, Fe2O3 and Pr6O11 have been introduced as potential optical elements. The structure and size examination of NCs were executed by XRD, Raman, and FESEM. Pr6O11/Fe2O3/GO@PCL polymeric NC is exhibited Pr6O11, and Fe2O3 average size of 1.4, 0.4 µm, while average pores size 2.1 µm. As well, the Uv–Vis shows an absorption edge shifting along the x-axis that it begins with 3.1 eV for pure PCL, after that it declined to 1.7 eV for Pr6O11@PCL NC. Also, Pr6O11 @PCL, and Pr6O11/ Fe2O3@PCL NCs show the lowest similar contact angle with 38°. Regarding cell attachment evaluation test, the Pr6O11/Fe2O3/GO@PCL NC healing valuation is touched ∼ 80%. As a result, the structure enabled 3-dimensional the division of normal cells, so promoting wound healing. 相似文献
182.
Lingpu Zhang Nicolás Montesdeoca Dr. Johannes Karges Prof. Dr. Haihua Xiao 《Angewandte Chemie (International ed. in English)》2023,62(21):e202300662
Cancer is one of the deadliest diseases worldwide. Recent statistics have shown that metastases and tumor relapse are the leading causes of cancer-associated deaths. While traditional treatments are able to efficiently remove the primary tumor, secondary tumors remain poorly accessible. Capitalizing on this there is an urgent need for novel treatment modalities. Among the most promising approaches, increasing research interest has been devoted to immunogenic cell death inducing agents that are able to trigger localized cell death of the cancer cells as well as induce an immune response inside the whole organism. Preliminary studies have shown that immunogenic cell death inducing compounds could be able to overcome metastatic and relapsing tumors. Herein, the application of metal complexes as immunogenic cell death inducing compounds is systematically reviewed. 相似文献
183.
Hong Zhang Chenxu Zhao Jianxi Yao Wallace C. H. Choy 《Angewandte Chemie (International ed. in English)》2023,62(24):e202219307
Advancing inverted (p-i-n) perovskite solar cells (PSCs) is critical for commercial applications given their compatibility with different bottom cells for tandem photovoltaics, low-temperature processability (≤100 °C), and promising operational stability. Although inverted PSCs have achieved an efficiency of over 25 % using doped or expensive organic hole transport materials (HTMs), their synthesis cost and stability still cannot meet the requirements for their commercialization. Recently, dopant-free and low-cost non-stoichiometric nickel oxide nanocrystals (NiOx NCs) have been extensively studied as a low-cost and effective HTM in perovskite optoelectronics. In this minireview, we summarize the synthesis and surface-functionalization methods of NiOx NCs. Then, the applications of NiOx NCs in other perovskite optoelectronics beyond photovoltaics are discussed. Finally, we provide a perspective for the future development of NiOx NCs for the commercialization of perovskite optoelectronics. 相似文献
184.
Yu Wang Bochun Liang Jiaxiong Zhu Geng Li Qing Li Ruquan Ye Jun Fan Chunyi Zhi 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302583
Constructing a reliable solid-electrolyte interphase (SEI) is imperative for enabling highly reversible zinc metal (Zn0) electrodes. Contrary to conventional “bulk solvation” mechanism, we found the SEI structure is dominated by electric double layer (EDL) adsorption. We manipulate the EDL adsorption and Zn2+ solvation with ether additives (i.e. 15-crown-5, 12-crown-4, and triglyme). The 12-crown-4 with medium adsorption on EDL leads to a layer-structured SEI with inner inorganic ZnFx/ZnSx and outer organic C−O−C components. This structure endows SEI with high rigidness and strong toughness enabling the 100 cm2 Zn||Zn pouch cell to exhibit a cumulative capacity of 4250 mAh cm−2 at areal-capacity of 10 mAh cm−2. More importantly, a 2.3 Ah Zn||Zn0.25V2O5⋅n H2O pouch cell delivers a recorded energy density of 104 Wh Lcell−1 and runs for >70 days under the harsh conditions of low negative/positive electrode ratio (2.2 : 1), lean electrolyte (8 g Ah−1), and high-areal-capacity (≈13 mAh cm−2). 相似文献
185.
Dr. Shi Tang Dr. Zhi Wang Yanzi Xu Huili Ma Dr. Jia Wang Dr. Christian Larsen Prof. Dongfeng Dang Prof. Ergang Wang Prof. Ludvig Edman 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302874
The emission efficiency of organic semiconductors (OSCs) often suffers from aggregation caused quenching (ACQ). An elegant solution is aggregation-induced emission (AIE), which constitutes the design of the OSC so that its morphology inhibits quenching π–π interactions and non-radiative motional deactivation. The light-emitting electrochemical cell (LEC) can be sustainably fabricated, but its function depends on motion of bulky ions in proximity of the OSC. It is therefore questionable whether the AIE morphology can be retained during LEC operation. Here, we synthesize two structurally similar OSCs, which are distinguished by that 1 features ACQ while 2 delivers AIE. Interestingly, we find that the AIE-LEC significantly outperforms the ACQ-LEC. We rationalize our finding by showing that the AIE morphology remains intact during LEC operation, and that it can feature appropriately sized free-volume voids for facile ion transport and suppressed non-radiative excitonic deactivation. 相似文献
186.
Mitsunori Fukaya Shota Nagamine Dr. Taro Ozaki Yaping Liu Miina Ozeki Taro Matsuyama Dr. Kazunori Miyamoto Prof. Dr. Hirokazu Kawagishi Prof. Dr. Masanobu Uchiyama Prof. Dr. Hideaki Oikawa Dr. Atsushi Minami 《Angewandte Chemie (International ed. in English)》2023,62(44):e202308881
Mushroom terpenoids are biologically and chemically diverse fungal metabolites. Among them, melleolides are representative sesquiterpenoids with a characteristic protoilludane skeleton. In this study, we applied a recently established hot spot knock-in method to elucidate the biosynthetic pathway leading to 1α-hydroxymelleolide. The biosynthesis of the sesquiterpene core involves the cytochrome P450 catalyzing stepwise hydroxylation of the Δ6-protoilludene framework and a stereochemical inversion process at the C5 position catalyzed by short-chain dehydrogenase/reductase family proteins. The highlight of the biosynthesis is that the flavoprotein Mld7 catalyzes an oxidation-triggered double-bond shift accompanying dehydration and acyl-group-assisted substitution with two different nucleophiles at the C6 position to afford the Δ7-protoilludene derivatives, such as melleolide and armillarivin. The complex reaction mechanism was proposed by DFT calculations. Of particular importance is that product distribution is regulated by interaction with the cell membrane. 相似文献
187.
Shuyan Gong Mingze Sun Yiyang Lee Nigel Becknell Jiangwei Zhang Zhongqi Wang Liang Zhang Zhiqiang Niu 《Angewandte Chemie (International ed. in English)》2023,62(4):e202214516
Single crystal surfaces with highly coordinated sites very often hold high specific activities toward oxygen reduction reaction (ORR) and others. Transposing their high specific activity to practical high-surface-area electrocatalysts remains challenging. Here, ultrathin Pt(100) alloy surface is constructed via epitaxial growth. The surface shows 3.1–6.9 % compressive strain and bulk-like characteristics as demonstrated by site-probe reactions and different spectroscopies. Its ORR activity exceeds that of bulk Pt3Ni(100) and Pt(111) and presents a 19-fold increase in specific activity and a 13-fold increase in mass activity relative to commercial Pt/C. Moreover, the electrochemically active surface area (ECSA) is increased by 4-fold compared to traditional thin films (e.g. NSTF), which makes the catalyst more tolerant to voltage loss at high current densities under fuel cell operation. This work broadens the family of extended surface catalysts and highlights the knowledge-driven approach in the development of advanced electrocatalysts. 相似文献
188.
This paper discusses the effects of adding particulate filler to a system undergoing liquid–liquid thermally induced phase separation (L–L TIPS). While much is known about the growth of droplets in L–L TIPS, little is known about the effect particular fillers have on droplet growth and the final cell size in the resulting microporous membranes. In this work, zeolite particles are shown to have a significant effect on the final cell size of these microporous membranes, the extent of which depends on the particle loading and processing conditions used to form the membrane. Two polymer–diluent–zeolite systems are reported: isotactic polypropylene–diphenyl ether and poly(methyl methacrylate)–cyclohexanol, both with zeolite 4A particles. 相似文献
189.
We studied the topographical effect of roughness displayed by a closely packed particle monolayer on formation of a cell monolayer (cell sheet). Particle monolayers were prepared by Langmuir-Blodgett deposition using particles, which were 527nm (SA053) and 1270nm (SA127) in diameter. Human umbilical vein endothelial cells (HUVECs) were seeded at a high density (2.0 x10(5)cells/cm(2)) onto particle monolayers. It was found that cells gradually became into contact with adjacent cells on the SA053 monolayer and the formed cell sheet could be readily detached from the particle monolayer by gentle pipetting. On the other hand, cells adhering onto the tissue culture polystyrene (TCPS) and the SA127 particle monolayer were difficult to peel off. At a low cell seeding density (5.0x10(4)cells/cm(2)), pre-coating with bovine plasma fibronectin (FN) allowed cell growth on an SA053 particle monolayer, and a confluent monolayer was able to be peeled as a cell sheet from the particle monolayer just by pipetting. By immunostaining of human fibronectin, we found that fibronectin was secreted and concentrated onto the substrate side of a cell sheet. The obtained cell sheet adhered and grew on the TCPS again within 20min. 相似文献
190.
In the last decade, cell elasticity has been widely investigated as a potential label free indicator for cellular alteration in different diseases, cancer included. Cell elasticity can be locally measured by pulling membrane tethers, stretching or indenting the cell using optical tweezers. In this paper, we propose a simple approach to perform cell indentation at pN forces by axially moving the cell against a trapped microbead. The elastic modulus is calculated using the Hertz-model. Besides the axial component, the setup also allows us to examine the lateral cell–bead interaction. This technique has been applied to measure the local elasticity of HBL-100 cells, an immortalized human cell line, originally derived from the milk of a woman with no evidence of breast cancer lesions. In addition, we have studied the influence of substrate stiffness on cell elasticity by performing experiments on cells cultured on two substrates, bare and collagen-coated, having different stiffness. The mean value of the cell elastic modulus measured during indentation was 26±9 Pa for the bare substrate, while for the collagen-coated substrate it diminished to 19±7 Pa. The same trend was obtained for the elastic modulus measured during the retraction of the cell: 23±10 Pa and 13±7 Pa, respectively. These results show the cells adapt their stiffness to that of the substrate and demonstrate the potential of this setup for low-force probing of modifications to cell mechanics induced by the surrounding environment (e.g. extracellular matrix or other cells). 相似文献