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Ihr gegenüber steht der Reduktionismus, in dessen Weltbild alle Objekte und Eigenschaften auf eine einzige Entität zurückzuführen sind, oder dass das Ganze nicht mehr als die Summe seiner Teile sei. Ein gutes Beispiel dafür, dass ein System deutlich mehr sein kann als die Summe seiner Teile, ist die aggregationsinduzierte Emission (AIE): Das Aggregat besitzt eine Eigenschaft (nämlich eine Lumineszenz), die seinen molekularen Bestandteilen komplett fehlt! Das AIE-Heft deckt eine Vielfalt an Themen ab, von bahnbrechenden Fortschritten bei den Strukturen und Mechanismen bis hin zu Anwendungsplattformen für Prozesstechnik, Informationsverschlüsselung, Bildschirme, Sensoren, Bildgebung und Theranostik. [Extracted from the article]

Endo/lysosomal escape of gene vectors and the subsequent unpacking of nucleic acids in cytosol are two major challenges for efficient gene delivery. Herein, we report a polymeric gene delivery vector, which consists of a photosensitizer (PS) with aggregation-induced emission (AIE) characteristics and oligoethylenimine (OEI) conjugated via an aminoacrylate (AA) linker that can be cleaved by reactive oxygen species (ROS). In aqueous media, the polymer could self-assemble into bright red fluorescent nanoparticles (NPs), which can efficiently bind to DNA through electrostatic interaction for gene delivery. Upon visible light irradiation, the generated ROS can break the endo/lysosomal membrane and the polymer, resulting in light-controlled endo/lysosomal escape and unpacking of DNA for efficient gene delivery. The smart polymer represents the first successful gene vector to simultaneously address both challenges with a single light excitation process. [ABSTRACT FROM AUTHOR]

The self‐assembly of highly stable zirconium(IV)‐based coordination cages with aggregation induced emission (AIE) molecular rotors for in vitro bio‐imaging is reported. The two coordination cages, NUS‐100 and NUS‐101, are assembled from the highly stable trinuclear zirconium vertices and two flexible carboxyl‐decorated tetraphenylethylene (TPE) spacers. Extensive experimental and theoretical results show that the emissive intensity of the coordination cages can be controlled by restricting the dynamics of AIE‐active molecular rotors though multiple external stimuli. Because the two coordination cages have excellent chemical stability in aqueous solutions (pH stability: 2–10) and impressive AIE characteristics contributed by the molecular rotors, they can be employed as novel biological fluorescent probes for in vitro live‐cell imaging. [ABSTRACT FROM AUTHOR]

Protected by the host cells, the hidden intracellular bacteria are typically difficult to kill by common antibiotics and cannot be visualized without complex cellular pretreatments. Herein, we successfully developed a bacteria‐metabolizable dual‐functional probe TPEPy‐d‐Ala, which is based on d‐alanine and a photosensitizer with aggregation‐induced emission for fluorescence turn‐on imaging of intracellular bacteria in living host cells and photodynamic ablation in situ. Once metabolically incorporated into bacterial peptidoglycan, the intramolecular motions of TPEPy‐d‐Ala are inhibited, leading to an enhanced fluorescent signal, which allows the clear visualization of the intracellular bacteria. Moreover, TPEPy‐d‐Ala can effectively ablate the labeled intracellular bacteria in situ owing to covalent ligation to peptidoglycan, yielding a low intracellular minimum inhibitory concentration (MIC) of 20±0.5 μg mL−1, much more efficient than that of a commonly used antibiotic, vancomycin. [ABSTRACT FROM AUTHOR]

Monitoring of human serum albumin (HSA) in a point‐of‐care fashion is urgently needed in particular for elderly or chronically ill patients. Herein, a dual‐state emissive chalcone probe having the feature of aggregation‐induced emission was designed and synthesized. The concentration of HSA can be evaluated by the ratios of emission from probes in aggregated and monomeric state, which gives a visually discernible red‐to‐green color change. A simple, portable paper‐based analytical device have been fabricated by integration of the recognition probe in the detection pad and employed for HSA test using the whole blood samples. This paper‐based assay shows the analytical capability comparable to the standard testing methods but is in a point‐of‐care fashion, providing a promising tool for at‐home HSA detection and HSA‐related disease diagnosis. [ABSTRACT FROM AUTHOR]

Traditional photosensitizers (PSs) show reduced singlet oxygen (1O2) production and quenched fluorescence upon aggregation in aqueous media, which greatly affect their efficiency in photodynamic therapy (PDT). Meanwhile, non‐targeting PSs generally yield low efficiency in antibacterial performance due to their short lifetimes and small effective working radii. Herein, a water‐dispersible membrane anchor (TBD‐anchor) PS with aggregation‐induced emission is designed and synthesized to generate 1O2 on the bacterial membrane. TBD‐anchor showed efficient antibacterial performance towards both Gram‐negative (Escherichia coli) and Gram‐positive bacteria (Staphylococcus aureus). Over 99.8 % killing efficiency was obtained for methicillin‐resistant S. aureus (MRSA) when they were exposed to 0.8 μm of TBD‐anchor at a low white light dose (25 mW cm−2) for 10 minutes. TBD‐anchor thus shows great promise as an effective antimicrobial agent to combat the menace of multidrug‐resistant bacteria. [ABSTRACT FROM AUTHOR]

The detection and elimination of intracellular bacteria remain a major challenge. In this work, we report an aggregation‐induced emission (AIE) bioprobe that can detect bacterial infection and kill bacteria surviving inside macrophages through a dynamic process, notably specific molecular tailoring of the probe by caspase‐1 activation in infected macrophages and accumulation of the residue on phagosomes containing bacteria, leading to light‐up fluorescent signals. Moreover, the AIEgen can serve as a photosensitizer for generation of reactive oxygen species (ROS); and the average ROS indicator fluorescent signal intensity per unit area in the bacterial phagosomes is approximately 2.7‐fold higher than that in the cytoplasm. This, in turn, induces bacteria killing with high efficiency and minimal cytotoxicity towards macrophages. We envision that this specific light‐up bioprobe may provide a new approach for selective and sensitive detection and eradication of intracellular bacterial infections. [ABSTRACT FROM AUTHOR]

Liposomes have been used as popular drug delivery systems for cancer therapy. However, it is difficult to track traditional liposome delivery systems in an efficient and stable fashion to assess their delivery efficacy and biodistribution after administration. Meanwhile, conventional fluorescent liposomes containing optical tracers face the challenge of aggregation‐caused quenching. Herein, we report a strategy for the integration of an aggregation‐induced emission fluorogen with a liposome to yield an AIEgen–lipid conjugate, termed "AIEsome". The AIEsome exhibits bright red fluorescence along with great photostability and biocompatibility, and can be used for in vitro cancer cell labeling and in vivo tumor targeting. Meanwhile, benefiting from the excellent photosensitizing ability of the AIEgen and its good oxygen exposure in aqueous media, the AIEsome also performs well in efficient photodynamic therapy (PDT) for both in vitro cancer cell ablation and in vivo antitumor therapy after white light illumination. [ABSTRACT FROM AUTHOR]

Abstract: Bio‐orthogonal tumor labeling is more effective in delivering imaging agents or drugs to a tumor site than active targeting strategy owing to covalent ligation. However, to date, tumor‐specific imaging through bio‐orthogonal labeling largely relies on body clearance to differentiate target from the intrinsic probe signal owing to the lack of light‐up probes for in vivo bio‐orthogonal labeling. Now the first light‐up probe based on a fluorogen with aggregation‐induced emission for in vivo bio‐orthogonal fluorescence turn‐on tumor labeling is presented. The probe has low background fluorescence in aqueous media, showing negligible non‐specific interaction with normal tissues. Once it reacts with azide groups introduced to tumor cells through metabolic engineering, the probe fluorescence is lightened up very quickly, enabling rapid tumor‐specific imaging. The photosensitizing ability was also used to realize effective image‐guided photodynamic tumor therapy. [ABSTRACT FROM AUTHOR]

The isomerization and optical properties of the cis and trans isomers of tetraphenylethene (TPE) derivatives with aggregation-induced emission (AIEgens) have been sparsely explored. We have now observed the tautomerization-induced isomerization of a hydroxy-substituted derivative, TPETH-OH, under acidic but not under basic conditions. Replacing the proton of the hydroxy group in TPETH-OH with an alkyl group leads to the formation of TPETH-MAL, for which the pure cis and trans isomers were obtained and characterized by HPLC analysis and NMR spectroscopy. Importantly, cis-TPETH-MAL emits yellow fluorescence in DMSO at −20 °C whereas trans-TPETH-MAL shows red fluorescence under the same conditions. Moreover, the geometry of cis- and trans-TPETH-MAL remains unchanged when they undergo thiol-ene reactions to form cis- and trans-TPETH-cRGD, respectively. Collectively, our findings improve our fundamental understanding of the cis/ trans isomerization and photophysical properties of TPE derivatives, which will guide further AIEgen design for various applications. [ABSTRACT FROM AUTHOR]

Subcellular organelle-specific reagents for simultaneous tumor targeting, imaging, and treatment are of enormous interest in cancer therapy. Herein, we present a mitochondria-targeting probe (AIE-mito-TPP) by conjugating a triphenylphosphine (TPP) with a fluorogen which can undergo aggregation-induced emission (AIE). Owing to the more negative mitochondrial membrane potential of cancer cells than normal cells, the AIE-mito-TPP probe can selectively accumulate in cancer-cell mitochondria and light up its fluorescence. More importantly, the probe exhibits selective cytotoxicity for studied cancer cells over normal cells. The high potency of AIE-mito-TPP correlates with its strong ability to aggregate in mitochondria, which can efficiently decrease the mitochondria membrane potential and increase the level of intracellular reactive oxygen species (ROS) in cancer cells. The mitochondrial light-up probe provides a unique strategy for potential image-guided therapy of cancer cells. [ABSTRACT FROM AUTHOR]