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1.
Small ; : e2204029, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36084169

RESUMO

In this work, a near-ultraviolet (NUV) emitter, 2MCz-CNMCz, with hot-exciton property is designed based on a "long-short axis" strategy, which exhibits good thermal stability, bipolar carrier transport ability, and high T1 energy level. Its nondoped NUV organic light-emitting diode (OLED) achieves a record maximum external quantum efficiency (ηext ) of 7.76%, with a peak at 404 nm and CIE coordinates of (0.158, 0.039). The corresponding high exciton utilization efficiency (ηr ) in the electroluminescence process reveals its potential as a functional sensitizing host. As expected, the TBPe-based blue fluorescent OLED with 2MCz-CNMCz as the host material shows better efficiency and lower efficiency roll-off than that with traditional host material mCP. Meanwhile, the Ir complexes-based green/yellow/red phosphorescent OLEDs with 2MCz-CNMCz host are also fabricated, reaching high ηext values of 26.1%, 30.4%, and 20.4%, respectively, and displaying negligible efficiency roll-offs at 1000 cd m-2 , which are among the best OLED performances based on the same emitters. To the authors' best knowledge, this is the first report on the design of high-quality universal and functional host material, and may bring new inspiration to the preparation of high-efficiency, low roll-off, full-color OLEDs.

2.
Nat Commun ; 13(1): 5154, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056014

RESUMO

Improving power efficiency (PE) and reducing roll-off are of significant importance for the commercialization of white organic light-emitting diodes (WOLEDs) in consideration of energy conservation. Herein, record-beating PE of 130.7 lm W-1 and outstanding external quantum efficiency (EQE) of 31.1% are achieved in all-fluorescence two-color WOLEDs based on a simple sandwich configuration of emitting layer consisting of sky-blue and orange delayed fluorescence materials. By introducing a red fluorescence dopant, all-fluorescence three-color WOLEDs with high color rendering index are constructed based on an interlayer sensitization configuration, furnishing ultrahigh PE of 110.7 lm W-1 and EQE of 30.8%. More importantly, both two-color and three-color WOLEDs maintain excellent PEs at operating luminance with smaller roll-offs than the reported state-of-the-art WOLEDs, and further device optimization realizes outstanding comprehensive performances of low driving voltages, large luminance, high PEs and long operational lifetimes. The underlying mechanisms of the impressive device performances are elucidated by host-tuning effect and electron-trapping effect, providing useful guidance for the development of energy-conserving all-fluorescence WOLEDs.

4.
Biosensors (Basel) ; 12(9)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36140107

RESUMO

Photodynamic therapy (PDT), emerging as a minimally invasive therapeutic modality with precise controllability and high spatiotemporal accuracy, has earned significant advancements in the field of cancer and other non-cancerous diseases treatment. Thereinto, type I PDT represents an irreplaceable and meritorious part in contributing to these delightful achievements since its distinctive hypoxia tolerance can perfectly compensate for the high oxygen-dependent type II PDT, particularly in hypoxic tissues. Regarding the diverse type I photosensitizers (PSs) that light up type I PDT, aggregation-induced emission (AIE)-active type I PSs are currently arousing great research interest owing to their distinguished AIE and aggregation-induced generation of reactive oxygen species (AIE-ROS) features. In this review, we offer a comprehensive overview of the cutting-edge advances of novel AIE-active type I PSs by delineating the photophysical and photochemical mechanisms of the type I pathway, summarizing the current molecular design strategies for promoting the type I process, and showcasing current bioapplications, in succession. Notably, the strategies to construct highly efficient type I AIE PSs were elucidated in detail from the two aspects of introducing high electron affinity groups, and enhancing intramolecular charge transfer (ICT) intensity. Lastly, we present a brief conclusion, and a discussion on the current limitations and proposed opportunities.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36149752

RESUMO

Compared with conventional closed-shell fluorophores, radical cations provide an opportunity for development of red-to-NIR fluorophores with small sizes and easy preparation. However, most radical cations reported in the literature suffer from poor stability in water solution and are almost non-emissive. To tackle this challenge, we herein develop a deep-red-emissive and water-stable pyrrole radical cation P •+ -DPA-Zn, which can be easily generated from P-DPA-Zn by air oxidation. The deep-red-emissive P •+ -DPA-Zn can be used for imaging-guided mitochondria-targeted delivery of Zn 2+ into cancer cells to promote mutant p53 proteins degradation and abrogate mutp53-manifested gain of function, including reduced chemotherapy resistance, inhibited cancer cell migration, decreased tumor cell colony and sphere formation. The water-stable and deep-red emissive pyrrole radical cation is thus promising for cancer theranostic applications.

6.
Biomaterials ; 289: 121767, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36099711

RESUMO

The endoplasmic reticulum (ER) plays essential roles in various physiological processes and is intimately connected to kinds of diseases. The development of ER-targeting theranostic agents is highly demanded for precise treatments, however, the effective and referential strategies for the construction of ER-targeting probes are limited. Herein, we developed series of ER-targeting luminogens based on keto-salicylaldehyde azine (KSA) framework by introducing phenolic hydroxyl group, which present good theranostic performance with selective enrichment in ER. Under systematical structure modulation, the key role of phenolic hydroxyl group at K-terminal in ER-targeting was experimentally confirmed. Besides, the cyanobenzyl moiety at S-terminal can enhance the luminous efficiency and improve cellular uptake ability. Moreover, the generated reactive oxygen species (ROS) of these KSA derivatives can efficiently trigger ER stress to induce the apoptosis of cancer cells, resulting in the effective inhibition of tumor cells both in vitro and in vivo. Therefore, this feasible modification strategy of inserting phenolic hydroxyl group to common multi-aryl-based luminogens provides a reliable and referential approach for ER-targeting probe establishment.

7.
Adv Mater ; : e2207671, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36134528

RESUMO

Molecular aggregates with environmental responsive property are desired for their wide practical applications such as bio-probes. Here, we report a series of smart near-infrared (NIR) luminogens for hyperlipidemia (HLP) diagnosis. The aggregates of these molecules exhibit the twisted intramolecular charge transfer effect in aqueous medium, but aggregation-induced emission in high viscous medium due to the restriction of the intramolecular motion. We describe these aggregates, which can autonomously respond to different environments via switching of the aggregation state without changing their chemical structures, as "smart aggregates". Intriguingly, these luminogens demonstrate NIR-II and NIR-III luminescence with ultra-large Stokes shifts (> 950 nm). Both in vitro detection and in vivo imaging of HLP can be realized in a mouse model. Linear relationships exist between the emission intensity and multiple pathological parameters in blood samples of HLP patients. Thus, the design of smart aggregate facilitates rapid and accurate detection of HLP and provides a promising attempt in aggregate science. This article is protected by copyright. All rights reserved.

8.
Front Chem ; 10: 964615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105310

RESUMO

We now report that some chiral compounds, like alcohols, which are not sterically hindered atropisomers nor epimer mixtures, exhibit two sets of simultaneous NMR spectra in CDCl3. Some other chiral alcohols also simultaneously exhibit two different NMR spectra in the solid state because two different conformers, A and B had different sizes because their corresponding bond lengths and angles are different. These structures were confirmed in the same solid state by X-ray. We designate these as pseudo-resonance for a compound exhibiting several different corresponding lengths that simultaneously coexist in the solid state or liquid state. Variable-temperature NMR, 2D NMR methods, X-ray, neutron diffraction, IR, photo-luminesce (PL) and other methods were explored to study whether new aggregation states caused these heretofore unknown pseudo-resonance structures. Finally, eleven chiral alcohols or diols were found to co-exist in pseudo-resonance structures by X-ray crystallography in a search of the CDS database.

9.
Natl Sci Rev ; 9(8): nwab216, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36110901

RESUMO

Metal clusters are useful phosphors, but highly luminescent examples are quite rare. Usually, the phosphorescence of metal clusters is hindered by ambient O2 molecules. Transforming this disadvantage into an advantage for meaningful applications of metal clusters presents a formidable challenge. In this work, we used ligand engineering to judiciously prepare colour-tuneable and brightly emitting Cu(I) clusters that are ultrasensitive to O2 upon dispersion in a fluid solution or in a solid matrix. When the O2 scavenger dimethyl sulfoxide (DMSO) was used as the solvent, joint photo- and oxygen-controlled multicolour switches were achieved for the first time for metal cluster-based photopatterning and photo-anticounterfeiting. More importantly, an aggregation-induced barrier to oxygen, a new aggregation-induced emission mechanism for metal clusters, was proposed, providing a new pathway to realizing the intense emission of metal clusters in the aggregated state. These results are expected to promote the application of metal clusters and enrich the luminescence theory of metal cluster aggregates.

10.
ACS Appl Bio Mater ; 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36112526

RESUMO

It is well-known that bacterial infections will induce a variety of diseases in the clinic. In particular, the emergence of drug-resistant bacteria has increased the threat to human health. The development of multiple modes of therapy will effectively fight against drug-resistant bacterial infections. In this work, we covalently attached an AIE photosensitizer to the antibiotic of moxifloxacin hydrochloride (MXF-HCl) and synthesized an antibiotic derivative, MXF-R, with pharmacological activity and photodynamic activation. In infected cells, MXF-R showed enhanced fluorescence after it specifically binds to bacteria; thus, in situ visualization of the bacteria was realized. Notably, through chemo- and photodynamic therapy, MXF-R exhibited better antibacterial activity than its parent antibiotic in rapid sterilization, and it achieved effective killing for moxifloxacin resistant bacteria. In addition, MXF-R shows a broad-spectrum antibacterial effect and could be used in the recovery therapy of infected wounds in mice, demonstrative of a significant therapeutic effect and good biological safety. Thus, as a promising multifunctional antibacterial agent, MXF-R will have tremendous potential in in situ visualization study and killing of drug-resistant bacteria. This work provides an innovative strategy for solving critical disease through the combination of materials and biomedical sciences.

11.
Mater Today Bio ; 16: 100399, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36052153

RESUMO

Fluorescence imaging-guided surgery is one of important techniques to realize precision surgery. Although second near-infrared window (NIR-II) fluorescence imaging has the advantages of high resolution and large penetration depth in surgical navigation, its major drawback is that NIR-II images cannot be detected by our naked eyes, which demands a high hand-eye coordination for surgeons and increases the surgical difficulty. On the contrary, visible fluorescence can be observed by our naked eyes but has poor penetration. Here, we firstly propose a kind of NIR-II and visible fluorescence hybrid navigation surgery assisted via a cocktail of aggregation-induced emission nanoparticles (AIE NPs). NIR-II imaging helps to locate deep targeted tissues and judge the residual, and visible fluorescence offers an easily surgical navigation. We apply this hybrid navigation mode in different animals and systems, and verify that it can accelerate surgical process and compatible with a visible fluorescence endoscopy. To deepen the understanding of lymph node (LN) labelling, the distribution of NPs in LNs after local administration is initially analyzed by NIR-II fluorescence wide-filed microscopy, and two fates of the NPs are summarized. An alternative strategy which combines indocyanine green and berberine is also reported as a compromise for rapidly clinical translation.

12.
ACS Omega ; 7(34): 30582-30589, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36061658

RESUMO

Elemental sulfur is not traditionally considered as an afterglow material, even though it can be endowed with fluorescence properties through processing it into nanodots. Herein, we discovered that elemental sulfur powder could emit room temperature phosphorescence (RTP) with a lifetime of 3.7 ms. A long-lived (>12 s) afterglow emission at 77 K could also be observed by the naked eye. Detailed investigations suggested that such a special phenomenon was attributed to impurity-related traps coupled with conduction and valence bands. After the sulfur is processed into nanodots, the rigid environment formed by the cross-linking of the surface ligands could stabilize the excited charges from quenching. This results in the promotion of RTP intensity and lifetime to achieve an emission lifetime of 200 ms. These results confirm the unique RTP of elemental sulfur powder, and also suggest the potential of sulfur-based materials as versatile components for the development of RTP materials.

13.
ACS Nano ; 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36099405

RESUMO

Microalgae-based biofuels are receiving attention at the environmental, economic, and social levels because they are clean, renewable, and quickly produced. The green algae Chlorella vulgaris has been extensively studied in research laboratories and the biofuel industry as a model organism to increase lipid production to be cost-effective in commercial production. In this work, we utilized a lipid-droplet-specific luminogen with aggregation-induced emission (AIE) characteristics to increase the lipid production of C. vulgaris by fluorescent imaging and sorting of those algal cells with large and rich lipid droplets for subculturing. The AIE-active TPA-A enabled real-time monitoring of the size and number of lipid droplets in C. vulgaris during their growth period so that we can identify the best time for harvesting. Furthermore, the algae cells with high lipid content were identified and collected for subculturing by the technique of fluorescence-activated cell sorting (FACS). The lipid production in the generation of two successive selections was almost doubled compared to the generation with natural selection. This work demonstrated that the technologies of AIE and FACS could be applied together to improve the production of a third-generation biofuel.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36103452

RESUMO

Two chiral molecules 1 and 2 were designed and synthesized with a pyrene moiety directly linked to a chiral cholesterol moiety and connected through a methylene spacer, respectively. Influence of the spacer on their stimuli-responsive luminescence, chirality, and self-assembly behaviors was systematically investigated. Molecules 1 and 2 had similar aggregation-induced emission enhancement (AIEE) in solution, because of carrying the same fluorescence moiety. Both molecules displayed mechanochromism (MC) property but with different color contrast, whereas only 2 showed mechanoluminescence (ML) activity. When doping in liquid crystal molecule 5CB, both molecules induced the formation of chiral nematic liquid crystals (N*-LCs) with strong circularly polarized luminescence (CPL). Molecule 2 induced single handedness signal, irrespective of doping ratios, while 1-doped N*-LCs showed an inversion of CPL signal from negative to positive upon the increase of doping ratios. Molecules 1 and 2 also self-assembled into different coassemblies with 5CB. Their distinct behaviors were attributed to the influence of the methylene spacer, which caused different molecular conformation and steric bulkiness; accordingly, it changed intermolecular interactions and molecular packing of the two molecules and led to diverse chirality and luminescence. This work provided important model molecules to better understand the molecular structure-property relationship and guide the design of novel functional molecules.

15.
Biosens Bioelectron ; 215: 114582, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35933738

RESUMO

The discriminative detection of glutathione (GSH) from cysteine (Cys) remains a challenge because of their similarity in structure and chemical properties. This study reported a strategy for selective and sensitive detection of GSH based on the GSH-promoted blue fluorescence of UiO-66-NH2 and aggregation-enhanced emission (AEE) feature of orange emissive Cu nanoclusters (NCs). A relatively weak blue fluorescence of UiO-66-NH2 was converted to strong after reacting with GSH due to the rotation-restricted emission enhancement mechanism. In addition, the GSH-activated UiO-66-NH2 was further used as a template and reducing reagent for synthesizing orange-red AEE active Cu NCs composites (UiO-66-NH2@Cu NCs). A ratiometric fluorescence response was observed after forming UiO-66-NH2@Cu NCs, helping discriminate GSH over Cys. In addition, UiO-66-NH2@Cu NCs were further utilized for the detection of GSH in clinical samples. The present findings provide an efficient strategy to discriminate GSH over Cys and open a new door for utilizing and functionalizing metal-organic frameworks (MOFs) for various applications.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Cisteína/química , Glutationa/química , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas , Ácidos Ftálicos
16.
Adv Mater ; : e2110496, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008371

RESUMO

The incorporation of charged functional groups is effective to modulate the activity of molecular complexes for the CO2 reduction reaction (CO2 RR), yet long-term heterogeneous electrolysis is often hampered by catalyst leaching. Herein, an electrocatalyst of atomically thin, cobalt-porphyrin-based, ionic-covalent organic nanosheets (CoTAP-iCONs) is synthesized via a post-synthetic modification strategy for high-performance CO2 -to-CO conversion. The cationic quaternary ammonium groups not only enable the formation of monolayer nanosheets due to steric hindrance and electrostatic repulsion, but also facilitate the formation of a *COOH intermediate, as suggested by theoretical calculations. Consequently, CoTAP-iCONs exhibit higher CO2 RR activity than other cobalt-porphyrin-based structures: an 870% and 480% improvement of CO current densities compared to the monomer and neutral nanosheets, respectively. Additionally, the iCONs structure can accommodate the cationic moieties. In a flow cell, CoTAP-iCONs attain a very small onset overpotential of 40 mV and a stable total current density of 212 mA cm-2 with CO Faradaic efficiency of >95% at -0.6 V for 11 h. Further coupling the flow electrolyzer with commercial solar cells yields a solar-to-CO conversion efficiency of 13.89%. This work indicates that atom-thin, ionic nanosheets represent a promising structure for achieving both tailored activity and high stability.

17.
Biosens Bioelectron ; 216: 114614, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35995026

RESUMO

Visualization of immunocyte-microbe interaction is of great importance to reveal the physiological role and working mechanism of innate and adaptive immune system. The lack of rapid and stable microbial labeling platform and insufficient understanding of macrophage-microbe interaction may delay precautions that could be made. In this contribution, a clickable AIEgen, CDPP-NCS, containing a cationic pyridinium moiety for targeting bacteria and an isothiocyanate moiety for covalently bonding with amine groups, is successfully developed. With the advantages of excellent photostability and rapid bioconjugation with amine groups on the bacterial envelope, the processes of macrophage-bacterium interactions with subcellular resolution has been successfully captured using this clickable AIE probe. Therefore, the new clickable AIEgen is a powerful tool to study the interaction between cell and bacterium.


Assuntos
Técnicas Biossensoriais , Aminas , Bactérias , Corantes Fluorescentes , Isotiocianatos , Macrófagos
18.
Biomaterials ; 288: 121712, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35948495

RESUMO

Owing to high sensitivity, selectivity, and non-invasiveness, fluorescence has been widely applied in the biomedical and sensing fields. Among the pool of fluorescent probes, luminogens with aggregation-induced emission (AIE) characteristic exhibit unique strengths in biological applications. However, most reported AIE luminogens (AIEgens) require complicated synthetic procedures, which raise the costs and biocompatibility concerns, especially in biomedical imaging and therapy. In contrast, bioproduct-inspired AIEgens (BioAIEgens) can compensate for the weakness of synthetic AIEgens in terms of their high biocompatibility, low costs, and easy preparation. This review highlights the latest development of BioAIEgens discovered from natural herbs, as well as their potential biomedical and sensing applications. As nature is full of potential resources, studying AIEgens from natural herbs can facilitate the strength of AIE properties in diverse applications and offer more inspiration to the future BioAIEgen structural design and development.


Assuntos
Corantes Fluorescentes , Fluorescência , Corantes Fluorescentes/química
19.
Biomaterials ; 288: 121709, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35995625

RESUMO

Real-time intraoperative guidance is essential during various surgical treatment of many diseases. Aggregation-induced emission (AIE) materials have shown great potential for guiding surgeons during complex interventions, with the merits of deep tissue penetration, high quantum yield, high molar absorptivity, low background, good targeting ability and excellent photostability. Herein, we provided insights to design efficient AIE materials regarding three key parameters, i.e., deep-tissue penetration ability, high brightness of AIE luminogens (AIEgens), and precise tumor/other pathology nidus targeting strategies, for realizing better application of fluorescence image-guided surgery. Representative interdisciplinary achievements were outlined for the demonstration of this emerging field. Challenges and future opportunities of AIE materials were briefly discussed. The aim of this review is to provide a comprehensive view of AIE materials for intraoperative guidance for researchers and surgeons, and to inspire more further correlational studies in the new frontiers of image-guided surgery.


Assuntos
Neoplasias , Cirurgia Assistida por Computador , Fluorescência , Corantes Fluorescentes , Humanos
20.
J Am Chem Soc ; 144(33): 15391-15402, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35948438

RESUMO

Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) using small-molecule dyes has high potential for clinical use. However, many NIR-II dyes suffer from the emission quenching effect and extremely low quantum yields (QYs) in the practical usage forms. The AIE strategy has been successfully utilized to develop NIR-II dyes with donor-acceptor (D-A) structures with acceptable QYs in the aggregate state, but there is still large room for QY improvement. Here, we rationally designed a NIR-II emissive dye named TPE-BBT and its derivative (TPEO-BBT) by changing the electron-donating triphenylamine unit to tetraphenylethylene (TPE). Their nanoparticles exhibited ultrahigh relative QYs of 31.5% and 23.9% in water, respectively. By using an integrating sphere, the absolute QY of TPE-BBT nanoparticles was measured to be 1.8% in water. Its crystals showed an absolute QY of 10.4%, which is the highest value among organic small molecules reported so far. The optimized D-A interaction and the higher rigidity of TPE-BBT in the aggregate state are believed to be the two key factors for its ultrahigh QY. Finally, we utilized TPE-BBT for NIR-II photoluminescence (PL) and chemiluminescence (CL) bioimaging through successive CL resonance energy transfer and Förster resonance energy transfer processes. The ultrahigh QY of TPE-BBT realized an excellent PL imaging quality in mouse blood vessels and an excellent CL imaging quality in the local arthrosis inflammation in mice with a high signal-to-background ratio of 130. Thus, the design strategy presented here brings new possibilities for the development of bright NIR-II dyes and NIR-II bioimaging technologies.


Assuntos
Corantes Fluorescentes , Luminescência , Animais , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Camundongos , Imagem Óptica , Água
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