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Chen Qian Gang Wu Di Jiang Xiaona Zhao Hai‐Bo Chen Yunze Yang Xian‐Wei Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(13):4261-4264
The development of optical imaging techniques has led to significant advancements in single‐nanoparticle tracking and analysis, but these techniques are incapable of label‐free selective nanoparticle recognition. A label‐free plasmonic imaging technology that is able to identify different kinds of nanoparticles in water is now presented. It quantifies the plasmonic interferometric scattering patterns of nanoparticles and establishes relationships among the refractive index, particle size, and pattern both numerically and experimentally. Using this approach, metallic and metallic oxide particles with different radii were distinguished without any calibration. The ability to optically identify and size different kinds of nanoparticles can provide a promising platform for investigating nanoparticles in complex environments to facilitate nanoscience studies, such as single‐nanoparticle catalysis and nanoparticle‐based drug delivery. 相似文献
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Jinbo Fei Luru Dai Fuping Gao Jie Zhao Junbai Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(22):7332-7336
Great success has been achieved in recent years in the development of synthetic or assembled nanobiomaterials. Among these, biomolecule‐based nanoarchitectures with special optical property are of particular interest. Here, we demonstrate that vitamin B2 nanocrystals assembled as nanorods can be obtained with precise control. Excitingly, such one‐dimensional nanostructures not only exhibit intrinsic optical waveguiding properties but also the ability to sensitize oxygen to produce reactive oxygen species. With these properties, we applied the obtained vitamin B2 nanorods under remotely localized light illumination into single tumour cells in vitro for anticancer photodynamic therapy. Further, vitamin B2 nanorods were explored for in vivo photodynamic therapy by using a tumour model. With such bionanostructures, new features and functions of vitamin B2 and its derivatives have been developed. 相似文献
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Shang‐Fu Yuan Cong‐Qiao Xu Jun Li Quan‐Ming Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):5967-5970
A golden fullerene Au32 cluster has been synthesized with amido and phosphine ligands as the protecting agents. Single‐crystal X‐ray structural analysis revealed that this gold nanocluster, [Au32(Ph3P)8(dpa)6] (SbF6)2 (Hdpa=2,2′‐dipyridylamine), has a stable pseudo‐Ih Au328+ core with S6 symmetry, which features an Au12@Au20 Keplerate cage co‐protected by Ph3P and dpa ligands. Quantum‐chemical studies were conducted to elucidate the origin of the special stability of this cluster, and suggest that it is electronically stabilized through metal–ligand interactions. 相似文献
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Liulin Wang Wei Du Zhangjun Hu Kajsa Uvdal Lin Li Wei Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14164-14181
Fluorophores and probes are invaluable for the visualization of the location and dynamics of gene expression, protein expression, and molecular interactions in complex living systems. Rhodamine dyes are often used as scaffolds in biological labeling and turn‐on fluorescence imaging. To date, their absorption and emission spectra have been expanded to cover the entire near‐infrared region (650–950 nm), which provides a more suitable optical window for monitoring biomolecular production, trafficking, and localization in real time. This review summarizes the development of rhodamine fluorophores since their discovery and provides strategies for modulating their absorption and emission spectra to generate specific bathochromic‐shifts. We also explain how larger Stokes shifts and dual‐emissions can be obtained from hybrid rhodamine dyes. These hybrid fluorophores can be classified into various categories based on structural features including the alkylation of amidogens, the substitution of the O atom of xanthene, and hybridization with other fluorophores. 相似文献
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Xing Huang Detre Teschner Maria Dimitrakopoulou Alexey Fedorov Benjamin Frank Ralph Kraehnert Frank Rosowski Harry Kaiser Stephan Schunk Christiane Kuretschka Robert Schlgl Marc‐Georg Willinger Annette Trunschke 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8801-8805
The direct conversion of syngas to ethanol, typically using promoted Rh catalysts, is a cornerstone reaction in CO2 utilization and hydrogen storage technologies. A rational catalyst development requires a detailed structural understanding of the activated catalyst and the role of promoters in driving chemoselectivity. Herein, we report a comprehensive atomic‐scale study of metal–promoter interactions in silica‐supported Rh, Rh–Mn, and Rh–Mn–Fe catalysts by aberration‐corrected (AC) TEM. While the catalytic reaction leads to the formation of a Rh carbide phase in the Rh–Mn/SiO2 catalyst, the addition of Fe results in the formation of bimetallic Rh–Fe alloys, which further improves the selectivity and prevents the carbide formation. In all promoted catalysts, Mn is present as an oxide decorating the metal particles. Based on the atomic insight obtained, structural and electronic modifications induced by promoters are revealed and a basis for refined theoretical models is provided. 相似文献