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991.
Yumin Wang Dr. Xuemiao Yin Prof. Junfeng Chen Prof. Yaxing Wang Prof. Zhifang Chai Prof. Shuao Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):1900-1905
Scintillators are a unique class of luminescent materials with specific applications towards radiation detection. The emitters within state-of-the-art scintillators are mostly limited to bismuth, cerium, europium, thallium, lead, tungsten, etc. A shared feature of these elements is the relatively high atomic number, which is responsible for high radiation stopping power and radiation-induced luminescence. Searching for new scintillating materials is an essential target aiming at specific applications. In this Concept article, we will discuss our recent works on the topic of “uranyl-bearing scintillators”. As a virgin territory in this field, uranyl-bearing scintillators show intrinsic merits for designing new materials with X-ray detection capability, that is, the large photoelectric cross-section, high X-ray attenuation efficiency, and high crystal density. In addition, we also present challenges in the further development of the uranyl-bearing scintillators. 相似文献
992.
Xiaokan Yu Wenao Ouyang Dr. Hao Qiu Zhijun Zhang Prof. Zhimin Wang Prof. Bengang Xing 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(65):e202201966
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are essential oxidative metabolites of organisms, which are closely related to physiological, pathological and pharmacological processes. The accurate detection of ROS/RNS is important for the understanding of biological processes, monitoring of pharmacological effects, and predicting the course of disease. The recently developed NIR nanoprobes based on upconversion nanoparticles (UCNPs) hold great prospects in sensitive and deep-tissue detection of ROS/RNS, and considerable progress has been achieved so far. In this review, we systematically summarize the up-to-date advances of UCNPs-based near-infrared (NIR) probes for ROS/RNS sensing, and the potential challenges and perspectives for further research are also highlighted. We envision that such a research field will have a bright future for modern biomedical applications. 相似文献
993.
Andrew J. Carrod Francesco Graglia Dr. Louise Male Dr. Cécile Le Duff Peter Simpson Dr. Mohamed Elsherif Dr. Zubair Ahmed Dr. Haider Butt Guang-Xi Xu Prof. Kenneth Kam-Wing Lo Dr. Paolo Bertoncello Prof. Zoe Pikramenou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103541
Dual detection systems are of interest for rapid, accurate data collection in sensing systems and in vitro testing. We introduce an IrIII complex with a boronic acid receptor site attached to the 2-phenylpyridine ligand as an ideal probe with photo- and electrochemical signals that is sensitive to monosaccharide binding in aqueous solution. The complex displays orange luminescence at 618 nm, which is reduced by 70 and 40 % upon binding of fructose and glucose, respectively. The electro-chemiluminescent signal of the complex also shows a direct response to monosaccharide binding. The IrIII complex shows the same response upon incorporation into hydrogel matrices as in solution, thus demonstrating the potential of its integration into a device, as a nontoxic, simple-to-use tool to observe sugar binding over physiologically relevant pH ranges and saccharide concentrations. Moreover, the complex's luminescence is responsive to monosaccharide presence in cancer cells. 相似文献
994.
Hannah E. Hackney Dr. Marco Paladino Hao Fu Prof. Dr. Dennis G. Hall 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(63):14324-14329
This study describes the synthesis, structure, and photophysical properties of a new luminescent polyaromatic boronic acid scaffold, diazaboryl-naphthyl-ketones (DNKs). These stable compounds display extremely bright fluorescence, aggregation-induced emission, positive solvatochromism, and solid-state fluorescence. DFT calculations and X-ray crystallographic study revealed notable electronic and structural differences between these compounds and the parent diaminonaphthalene (DAN) adducts. Acylation of the DAN system causes a localization of both HOMO and LUMO onto the DNK unit, which validates the negligible influence of the B-aryl substituent. The LUMO energy is lowered, and its shape significantly altered. Photophysical data in solution and the solid state revealed blue-shifted, narrowed, and intense emissions for DNKs (up to 89 % quantum yield). The potential utility of the fluorogenic DNK system was demonstrated with a proof-of-concept for the determination of trace boronic acid contaminants in solid samples, down to one-ppm level, using HPLC with fluorescence detection. This method could be useful in pharmaceutical development for the quantitation of difficult-to-detect and potentially mutagenic residual boronic acid from late cross-coupling reactions in drug syntheses. 相似文献
995.
Duo Xi Yanzi Xu Ruohan Xu Zhi Wang Daomeng Liu Qifei Shen Ling Yue Prof. Dongfeng Dang Prof. Lingjie Meng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(12):2741-2748
To achieve a highly efficient, dual-state emission platform for picric acid (PA) detection and latent fingerprint (LFP) visualization, flexible alkyl chains have been facilely attached to the commercial organic dye 3,4,9,10-perylenetetracarboxylic dianhydride to provide the target perylenetetracarboxylate molecules PTCA-C4, PTCA-C6, and PTCA-C12. Interestingly, all these molecules exhibited impressive fluorescence characteristics with high photoluminescence quantum yields (PLQYs) of around 93.0 % in dilute solution. Also, emissive features were observed in the solid state because close molecular packing is prevented by the alkyl chains, especially for PTCA-C6, which has a high PLQY value of 49.0 %. Benefiting from its impressive fluorescence performance in both solution and as aggregates, PTCA-C6 was used as a dual-state emission platform for PA detection and also LFP visualization. For example, double-responsive fluorescence quenching in solution was observed in PA detection studies, resulting in high quenching constants (KSV) and also low limit-of-detection values. Furthermore, the fingerprint powder based on PTCA-C6 also presented an impressive performance on various substrates in terms of fluorescence intensity and resolution, clearly providing the specific fine details of latent fingerprints. These results demonstrate that the facilely synthesized PTCA-C6 with efficient dual-state emission exhibits great potential in the real-world applications of PA detection and LFP visualization. 相似文献
996.
Dr. Leandro Trupp Dr. Andrea C. Bruttomesso Dr. Svetlana V. Eliseeva Dr. Stéphane Petoud Dr. Javier A. Ramírez Dr. Beatriz C. Barja 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(55):12645-12653
Herein, the design, synthesis, and characterization of a phenhomazine ligand are described. The ligand has six pendant acetate arms designed for the combined coordination of copper(II) and lanthanide(III) ions, with the perspective of developing a “turn-off” copper sensor. The key step for the ligand preparation was the one-step endomethylene bridge fission of a diamino Tröger's base with a concomitant alkylation. Fluorescence and absorption spectroscopies as well as nuclear magnetic resonance (NMR) experiments were performed to analyze and understand the coordination properties of the ligand. Transition metal coordination was driven by the synergistic effect of the free nitrogen atoms of the diazocinic core and the two central acetate arms attached to those nitrogen atoms, whereas lanthanide coordination is performed by the external acetate arms, presumably forming a self-assembled 2:2 metallosupramolecular structure. The terbium complex shows the typical green emission with narrow bands and long luminescence lifetimes. The luminescence quenching produced by the presence of copper(II) ions was analyzed. This work sets, therefore, a starting point for the development of a phenhomazine-based “turn-off” copper(II) sensor. 相似文献
997.
Dr. Shadab Gharaati Cui Wang Dr. Christoph Förster Florian Weigert Dr. Ute Resch-Genger Prof. Dr. Katja Heinze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1003-1007
Photon upconversion has enjoyed increased interest in the last years due to its high potential for solar-energy harvesting and bioimaging. A challenge for triplet–triplet annihilation upconversion (TTA-UC) processes is to realize these features in solid materials without undesired phase segregation and detrimental dye aggregation. To achieve this, we combine a palladium porphyrin sensitizer and a 9,10-diphenylanthracene annihilator within a crystalline mesoporous metal–organic framework using an inverted design. In this modular TTA system, the framework walls constitute the fixed sensitizer, while caprylic acid coats the channels providing a solventlike environment for the mobile annihilator in the channels. The resulting solid material shows green-to-blue delayed upconverted emission with a luminescence lifetime of 373±5 μs, a threshold value of 329 mW cm−2 and a triplet–triplet energy transfer efficiency of 82 %. The versatile design allows straightforward changing of the acceptor amount and type. 相似文献
998.
Yuan Chen Baobao Sun Haohui Feng Ranran Wang Ming Cheng Dr. Peng Wang Zhiping Zhou Prof. Juli Jiang Prof. Leyong Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(48):12305-12309
Chirality at different levels is widely observed in nature, but the clue to connect it all together, and the way chirality transfers among different levels are still obscure. Herein, a l -/d -lysine-based self-assembly system was constructed, in which two-step chirality transfer among three different levels was observed in aqueous solution. The chirality originated from the point chirality of amino acid derivatives l -/d -PyLys hydrochloride, and was transferred to the planar conformational chirality of water-soluble pillar[5]arene pR-/pS-WP5. Then, with the aid of pR-/pS-WP5, nanoparticles were formed that exhibited L-/R-handed circularly polarized luminescence with a dissymmetry factor of up to ±0.001, arising from pyrene chiral excimers. This multilevel chirality transfer not only provides a perspective to trace potential clues, and to pursue certain ways by which the chirality transfers, but also offers a strategy to create controllable CPL emission in aqueous media. 相似文献
999.
Dr. Srestha Basu Archismita Hajra Chirantan Gayen Prof. Anumita Paul 《Chemphyschem》2020,21(8):809-813
Herein, we report discrimination of dicarboxylic acids – fumaric acid (FA) and maleic acid (MA) – exhibiting geometrical isomerism, using nanoclusters based luminescent probe having excitation under broad day light. The luminescent probe was designed via complexation reaction between zinc ions and ligands (mercaptopropioinc acid; MPA) stabilizing the gold nanoclusters. This resulted in formation of nanoaggregates exhibiting bright green luminescence upon excitation at 450 nm capable of discriminating between FA and MA upto nanomolar level. The basis of discrimination has been attributed to deprotonation of FA and MA following interaction with MPA moieties present on the surface of the nanoaggregates and being governed by the stability of the respective conjugate base of the geometrical isomers of the dicarboxylic acids. As a consequence of different extent of deprotonation of FA and MA upon interaction with the cluster aggregates, different effect on the luminescence of the aggregates was observed, thus enabling discernible fluorimetric discrimination between FA and MA under visible light excitation. 相似文献
1000.
S.P. Vinay Udayabhanu H.N. Sumedha G. Nagaraju S. Harishkumar N. Chandrasekhar 《应用有机金属化学》2020,34(10):e5830
Silver oxide nanoparticles (Ag2O NPs) were prepared using cantaloupe (Cucumis melo) seeds as a fuel by employing a green synthesis method. The prepared Ag2O NPs were investigated using powder X-ray diffraction (PXRD), UV–visible spectrum, Fourier transform infrared analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive spectroscopy, and photoluminescence studies. PXRD data reveal the establishment of cubic crystal structure of Ag2O NPs. According to SEM and TEM results, the morphology of the prepared NPs was agglomerated and spherical. The photodegradation activity of the prepared Ag2O NPs over methylene blue dye was promising under visible light irradiation. Furthermore, the antimicrobial assay of the synthesized Ag2O NPs was carried out by the disc diffusion method against Gram-positive and Gram-negative microbial strains. 相似文献