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oe1(光电查) - 科学论文

207 条数据
?? 中文(中国)
  • Controlling the Emergence and Shift Direction of Mechanochromic Luminescence Color of a Pyridine-Terminated Compound

    摘要: In this study, mechanochromic luminescence was induced in a complex of mechano-inactive compounds. Dye/acid complexes containing the same p-conjugated backbones was prepared. While the luminophore showed blue and red shifts in photoluminescence spectra when combined with different acids by grinding, it exhibited slight mechanoresponsiveness itself. Also, compounds with similar molecular backbones to the dye/acid complex were synthesized to clarify the color change mechanism. The compounds showed both blue and red shifts in photoluminescence and diffuse reflectance spectra upon grinding, indicating that mechanochromic luminescence in the hydrogen-bonded complex is like its monomeric analogue and that aggregation structure plays an important role in the mechanoresponsive behavior rather than p-conjugated structure. We showed that mechanoinduced color change can be induced by imitating mechanoresponsive compounds without synthetic modification.

    关键词: Luminescence,Supramolecular chemistry,Aggregation

    更新于2025-09-23 15:23:52

  • A Photostable AIEgen for Specific and Real-time Monitoring of Lysosomal Processes

    摘要: Lysosomes are recognized as advanced organelles involved in many cellular processes, and are also considered as crucial regulators of cell homeostasis. The current strategies for monitoring activities of lysosomes exhibit some limitations. Herein, we synthesized a novel fluorescent probe named 2M-DPAS with AIE characteristics, which was proved to have significant advantages of good biocompatibility, high selectivity, bright emission and excellent photostability. Based on those, 2M-DPAS can be used to continuously monitor the dynamic changes of lysosomes including autophagy and mitophagy, as well as to track the process of endocytosis of macromolecules in lysosomes, which are benefit to better know about the lysosomes-related diseases.

    关键词: Aggregation-induced emission,Lysosomes,Autophagy,Monitoring,Phagocytosis of macromolecules

    更新于2025-09-23 15:23:52

  • A cyanostilbene-based molecule with aggregation-induced emission properties: amplified spontaneous emission, protonation effect and electroluminescence

    摘要: A terpyridine-substituted cyanostilbene derivative (Z)-2-(4′-([2,2′:6′,2″-terpyridin]-4′-yl)-[1,1′-biphenyl]-4-yl)-3-phenylacrylonitrile (CNSTPy) was synthesized and characterized. The compound exhibits remarkable aggregation-induced emission phenomenon and its single crystal shows a blue emission with fluorescent efficiency as high as 45%. Based on its aggregation state behavior, multiple applications towards exploring its lasing, fluorescence switching and electroluminescence properties were realized. Amplified spontaneous emission (ASE) was observed from the crystal and verified by the variable pump strip method, with a threshold value of ~1.5 mJ cm?2. The protonation/deprotonation processes accompanied by the formation of different molecular aggregation structure result in the distinct blue and yellow emissions. Additionally, the molecule also shows a moderate electroluminescence performance.

    关键词: amplified spontaneous emission,cyanostilbene,aggregation-induced emission,protonation effect

    更新于2025-09-23 15:23:52

  • Subtle structure tailoring of metal-free triazine luminogens for highly efficient ultralong organic phosphorescence

    摘要: Highly efficient ultralong organic phosphorescence (UOP) based on a series of metal-free triazine luminogens was achieved via subtly structural tailoring of bromine substituted positions. Impressively, p-BrAT in solid state displayed high phosphorescence efficiency up to 9.7% with a long lifetime of 386 ms, which was one of the highest efficient UOP materials reported so far in metal-free compounds.

    关键词: Isomerism,Ultralong organic phosphorescence (UOP),Crystal engineering,H-Aggregation,Intermolecular interactions

    更新于2025-09-23 15:23:52

  • A Nanoprobe for Diagnosing and Mapping Lymphatic Metastasis of Tumor Using 3D Multispectral Optoacoustic Tomography Owing to Aggregation/Deaggregation Induced Spectral Change

    摘要: Lymphatic metastasis of tumor is one of leading causes of cancer-related death, and diagnosing lymphatic metastasis is of significance in terms of optimal disease management and possible better outcomes for patients. Herein a turn-on optoacoustic nanoprobe is reported for noninvasively diagnosing and locating lymphatic metastasis in vivo. A positively charged tricyanofuran-containing polyene chromophore (TCHM) with high extinction coefficient is designed, synthesized, and allowed to form the nanoprobe with a negatively charged hyaluronan. The TCHMs take an aggregated state within the nanoprobe and exhibit weak absorption at 882 nm, the overexpressed hyaluronidase in cancer cells specifically degrades hyaluronan into small fragments and disaggregates TCHMs, thereby greatly enhancing the absorption at 882 nm and generating prominent optoacoustic signals. For multispectral optoacoustic tomography (MSOT) imaging in vivo, mice models with subcutaneous tumor and orthotopic bladder tumor are imaged first to demonstrate the nanoprobe’s capability for detecting HAase-overexpressing tumors. A mouse model of lymphatic metastasis of tumor is then established and the lymphatic metastasis is successfully imaged and tracked optoacoustically. The imaging results were verified using multiple biochemical assays. Moreover, 3D MSOT renderings are obtained for precisely locating and tracking the metastasis of tumor in lymphatic system in a spatiotemporal manner.

    关键词: lymphatic metastasis,imaging,multispectral,nanoprobe,3D,optoacoustic tomography,aggregation

    更新于2025-09-23 15:23:52

  • Study of oil-particle-aggregation by digital inline holograph

    摘要: This study was performed to visually analyse the relationship between particles and oil in seawater by digital holograph technology. Two types of particles with different sizes were chosen to form oil-particle aggregates (OPAs) in the laboratory to determine whether these particles may be a good approach to safely and harmoniously recover marine environment after an oil spill. The processes were recorded by a digital inline holographic system, which could facilitate a continuous real-time three-dimensional in situ observation of oil droplets and OPAs without touching these particles. The visual results showed that, in the micro scale, the particles formed two different types of OPA after breaking the oil film and transported oil into the bottom of the water, while some OPAs could be resuspended.

    关键词: spatial distribution,oil droplet,oil particle aggregation,marine oil spill,digital holographic,digital generated hologram

    更新于2025-09-23 15:23:52

  • Novel rhodamine-based colorimetric and fluorescent sensor for the dual-channel detection of Cu2+ and Co2+/trivalent metal ions and its AIRE activities

    摘要: A rhodamine hydrazone 1 bearing coumarin moiety was designed and prepared. Compound 1 exhibited high selectivity toward Co2+ and trivalent metal ions with fluorescence enhancement in CH3OH solution. However, 1 selectively responded to Al3+ in nearly pure H2O media and was further applied to monitor Al3+ in live cells. Moreover, 1 could also act as a colorimetric probe toward Cu2+ in either CH3OH or H2O solution. In addition, sensor 1 displayed aggregation-induced ratiometric emission (AIRE) activities in mixed H2O/CH3OH solution.

    关键词: cell imaging,coumarin,fluorescent probe,Aggregation-induced ratiometric emission,metal ions,rhodamine

    更新于2025-09-23 15:23:52

  • Nuclear Spin Singlet States in Photoactive Molecules: From Fluorescence/NMR Bimodality to a Bimolecular Spin Singlet State Switch

    摘要: Nuclear spin singlet states are silent states in nuclear magnetic resonance (NMR). However, they can be probed indirectly and offer great potential for the development of contrast agents for magnetic resonance imaging (MRI). Here, we are introducing two novel concepts: Firstly, we investigate the bimodal NMR/fluorescence properties of 13C2-tetraphenylethylene. It possesses a long-lived singlet state in organic solvents, which shortens upon the addition of water. This simultaneously increases the fluorescence emission in a substantial enhancement of fluorescence. Secondly, we introduce a bimolecular singlet state switch based on 3-2H-coumarin containing an isolated proton. Upon UV-light exposure, a dimer forms leading to a coupling between two previously isolated protons. A nuclear spin singlet state can now be populated. Excitation with a wavelength of 254 nm results in partly cleavage of the molecule back into its monomer.

    关键词: Photoswitches,NMR spectroscopy,Aggregation induced emission,Fluorescence,Nuclear spin singlet state

    更新于2025-09-23 15:23:52

  • Facile fabrication of cross-linked fluorescent organic nanoparticles with aggregation-induced emission characteristic via the thiol-ene click reaction and their potential for biological imaging

    摘要: Over the past several years, the biomedical applications of fluorescent organic nanoparticles (FONs) with aggregation-induced emission (AIE) feature have been extensively explored because the AIE-active FONs could effectively overcome the aggregation caused quenching (ACQ) effect of FONs based on conventional organic dyes. The development of novel methods for synthesis of AIE-active FONs plays a centre role for their biomedical applications. In this work, we reported a facile one-step thiol-ene click reaction for fabrication of AIE-active FONs through conjugation of acrylated PEG and AIE-active tetraphenylethylene (TPE) with two ene bonds using pentaerythritol tetra(3-mercaptopropionate) as the linkage. The successful synthesis of TPE containing AIE-active copolymers was evidenced by various characterization techniques. The particle size and fluorescence properties of the resultant TPE-S-PEG copolymers were evaluated by transmission electronic microscopy and fluorescence spectroscopy. Moreover, the cell viability and cell uptake behavior was also examined to evaluate their potential for biological imaging. We demonstrated that the cross-linked TPE-S-PEG show small size, high water dispersibility, low cytotoxicity and strong fluorescence for tracing. All of these advantages endow the TPE-S-PEG FONs great potential for biological imaging applications. Furthermore, this novel click reaction can take place under mild experimental conditions with high efficiency. It could be also further expanded for preparation of multifunctional AIE-active materials due to the universality of the thiol-ene click reaction and good precursor applicapability. Taken together, we have developed a novel and effective thiol-ene click reaction to fabricate the cross-linked AIE-active FONs, which display excellent physicochemical and biological properties and are promising for biomedical applications.

    关键词: thiol-ene click reaction,Aggregation-induced emission,biomedical applications,fluorescent organic nanoparticles,cross-linked FONs

    更新于2025-09-23 15:23:52

  • An AIEgen-based fluorescent probe for highly selective and specific imaging of lipid droplets in L02 and HepG2 cells

    摘要: Lipid droplets (LDs), as dynamic organelles, are associated with physiologically and pathologically metabolic processes. Especially, in human liver cancer cells (HepG2 cells) the lipid metabolism shows significant difference by comparing with the human normal liver cell (L02 cells). In this work, a new highly selective and specific fluorescent probe TPA-SD for the detection of LDs has been rationally designed and easily prepared from triphenylamine and salicylaldehyde, which possesses aggregation-induced emission (AIE) and excited state intramolecular proton transfer characteristics (ESIPT). Ideal probes for LDs imaging require high concentration accumulation of fluorophores in LDs and lack of self-quenching in the aggregated state, so the AIE property is necessary. TPA-SD can successfully and specifically accumulate in LDs, thus facilitating clearly distinguishing L02 cells from HepG2 cells according to obvious difference in the number of dot-shaped LDs marked by TPA-SD. The dot-shaped LDs in the HepG2 cells is found to be obviously more than that in the L02 cells. Moreover, the spatial distribution of LDs could be identified by TPA-SD. The results indicate TPA-SD possesses great potential in imaging and diagnosis of LDs-related diseases.

    关键词: fluorescent probe,aggregation-induced emission,dot-shaped LDs number,lipid droplets (LDs) imaging

    更新于2025-09-23 15:23:52