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Schiff bases are a crucial component in various functional materials but often exhibit non‐emissive behavior which significantly limits their potential applications as luminescent materials. However, traditional approaches to convert them into aggregate emitters often require intricate molecular design, tedious synthesis, and significant time and resource consumption. Herein, we present a cocrystallization‐induced emission strategy that can transform non‐emissive (hetero)aryl‐substituted Schiff bases into green‐yellow to yellow aggregate emitters via even simple grinding of a mixture of Schiff bases and 1,2,4,5‐tetracyanobenzene (TCB) mixtures. The combined experimental and theoretical analysis revealed that the cocrystallization inhibits the C=N isomerization and promotes face‐to‐face π–π interaction, which restricts access to both the dark state and canonical intersection to ultimately induce emission. Furthermore, the induced emission enables the observation of solid‐state molecular diffusion through fluorescence signals, advancing white light emission diodes, and notably, solution‐processed organic light‐emitting diodes based on cocrystal for the first time. This study not only highlights the potential of developing new C=N structural motifs for AIEgens but also could boost advancements in related structure motifs like C=C and N=N. [ABSTRACT FROM AUTHOR]

The length and mode of conjugation directly affect the molecular electronic structure, which has been extensively studied in through‐bond conjugation (TBC) systems. Corresponding research greatly promotes the development of TBC‐based luminophores. However, how the length and mode of through‐space conjugation (TSC), one kind of weak interaction, influence the photophysical properties of non‐conjugated luminophores remains a relatively unexplored field. Here, we unveil a non‐linear relationship between TSC length and emission characteristics in non‐conjugated systems, in contrast to the reported proportional correlation in TBC systems. More specifically, oligo(phenylene methylene)s (OPM[4]‐OPM[7]) exhibit stronger TSC and prominent blue clusteroluminescence (CL) (≈440 nm) compared to shorter counterparts (OPM[2] and OPM[3]). OPM[6] demonstrates the highest solid‐state quantum yield (40 %), emphasizing the importance of balancing flexibility and rigidity. Further theoretical calculations confirmed that CL of these oligo(phenylene methylene)s was determined by stable TSC derived from the inner rigid Diphenylmethane (DPM) segments within the oligomers instead of the outer ones. This discovery challenges previous assumptions and adds a new dimension to the understanding of TSC‐based luminophores in non‐conjugated systems. [ABSTRACT FROM AUTHOR]

X‐ray imaging technology has achieved important applications in many fields and has attracted extensive attentions. Dynamic X‐ray flexible imaging for the real‐time observation of the internal structure of complex materials is the most challenging type of X‐ray imaging technology, which requires high‐performance X‐ray scintillators with high X‐ray excited luminescence (XEL) efficiency as well as excellent processibility and stability. Here, a macrocyclic bridging ligand with aggregation‐induced emission (AIE) feature was introduced for constructing a copper iodide cluster‐based metal–organic framework (MOF) scintillator. This strategy endows the scintillator with high XEL efficiency and excellent chemical stability. Moreover, a regular rod‐like microcrystal was prepared through the addition of polyvinyl pyrrolidone during the in situ synthesis process, which further enhanced the XEL and processibility of the scintillator. The microcrystal was used for the preparation of a scintillator screen with excellent flexibility and stability, which can be used for high‐performance X‐ray imaging in extremely humid environments. Furthermore, dynamic X‐ray flexible imaging was realized for the first time. The internal structure of flexible objects was observed in real time with an ultrahigh resolution of 20 LP mm−1. [ABSTRACT FROM AUTHOR]

Optimized theranostic strategies for Alzheimer's disease (AD) remain almost absent from bench to clinic. Current probes and drugs attempting to prevent β‐amyloid (Aβ) fibrosis encounter failures due to the blood–brain barrier (BBB) penetration challenge and blind intervention time window. Herein, we design a near‐infrared (NIR) aggregation‐induced emission (AIE) probe, DNTPH, via balanced hydrophobicity‐hydrophilicity strategy. DNTPH binds selectively to Aβ fibrils with a high signal‐to‐noise ratio. In vivo imaging revealed its excellent BBB permeability and long‐term tracking ability with high‐performance AD diagnosis. Remarkably, DNTPH exhibits a strong inhibitory effect on Aβ fibrosis and promotes fibril disassembly, thereby attenuating Aβ‐induced neurotoxicity. DNTPH treatment significantly reduced Aβ plaques and rescued learning deficits in AD mice. Thus, DNTPH serves as the first AIE in vivo theranostic agent for real‐time NIR imaging of Aβ plaques and AD therapy simultaneously. [ABSTRACT FROM AUTHOR]

Pathogenic bacteria infections, especially multidrug resistant bacteria infections have aroused worldwide attention due to their severe threats to human beings. Thus, the development of highly effective antibacterial reagents is very important. However, the design of antimicrobials is still quite challenging for the lack of a universal design strategy. Here, a synergistic manipulation strategy of dipole‐dipole and anion‐π+ interaction is proposed for constructing highly efficient antimicrobials with aggregation‐induced emission (AIE) feature. Firstly, four anion‐π+‐type AIE luminogens were designed and synthesized. Due to the electron‐donating and hydrophilic characteristic of methoxy groups, 3MOTPO containing three methoxy groups showed the largest dipole moment (5.06 Debye) and dual anion‐π+ interactions in the solid state. Driven by both dipole‐dipole and anion‐π+ interactions, 3MOTPO showed the strongest bacterial binding ability and the best antibacterial activities (MIC90=3.76 μM). The work offers a deep insight into the rational design of highly efficient antimicrobials for luminescence‐guided antibacterial study. [ABSTRACT FROM AUTHOR]

• Universal design principles for ratiometric AIEgen probes. • Versatile construction strategies of ratiometric AIEgen probes. • Representative seminal application examples of ratiometric AIEgen probes in biosensing and bioimaging. • Addressing current challenges and exploring future perspectives in the development of ratiometric AIEgen systems. Ratiometric fluorescence probes, with their inherent self-calibration capabilities, have become indispensable tools in the fields of biosensing and bioimaging. These probes can correct for factors that are independent of the target, making the development of innovative ratiometric fluorescent probes a highly sought-after endeavor. Aggregation-induced emission luminogens (AIEgens) do not emit when in solution but show strong emission when aggregated, thus opening up exciting avenues for designing and creating high-performance ratiometric fluorescence probes. This comprehensive review meticulously details the recent advancements in AIEgen-based ratiometric fluorescence probes. The discussion encompasses design principles, construction strategies, and sensing mechanisms. Subsequently, the review explores the diverse applications of ratiometric AIEgen probes, demonstrating their efficacy with seminal examples in biosensing and bioimaging. The concluding section addresses future prospects and current challenges. We believe that this review should inspire researchers to make further contributions to this intriguing field and aid in its progression. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advantages of lipid droplets-specific targeting AIE probes over conventional analogues were summarized. • Design insights into lipid droplets-specific targeting AIE probes were summarized. • In vitro lipid droplets imaging and biological applications of AIE probes were summarized. • In vivo lipid droplets imaging and biological applications of AIE probes were summarized. • Future outlooks surrounding the applications of AIE probes for lipid droplets were summarized. Lipid droplets (LDs) are organelles that have evolved to store intracellular neutral lipids and maintain cellular energy homeostasis. Once considered as inert fat particles, they have recently gained much attention. Along with the rapid development of research, LDs are captivating increasingly concern since being established to be dynamic and mobile, which is closely linked to metabolic disorders and diseases such as obesity, diabetes and cancer. Therefore, the development of reliable imaging tools that enable specific recognition and in-depth study of LDs is of great significance. Traditional dyes used for LDs fluorescence imaging may suffer from drawbacks of low signal-to-noise ratio, self-decomposition and aggregation-caused quenching phenomena, which severely hinder further studies and advances. In recent years, LDs targetable probes with aggregation-induced emission (AIE) property have arouse considerable interests because they offer an alternative solution for overcoming the aforementioned deficiencies. Typically, AIE fluorescence probes share multitude advantages in terms of excellent brightness as aggregates, large Stocks shifts, good photo-stability and high signal-to-noise ratio. In this review, the importance of LDs is introduced, and then the research progress of representative AIE fluorescence probes for LDs imaging and biological applications at cell, tissue and in vivo levels are separately discussed. [ABSTRACT FROM AUTHOR]

• Penetration of AIEgen-based nanomaterials across biological barriers were summarized. • Detection and diagnosis of brain diseases with AIEgens were summarized. • Bioimaging of the brain structure in health and disease were summarized. • Therapeutics for specific diseases in the brain using AIEgens were summarized. • Future outlooks surrounding the applications of AIEgens in the brain were summarized. The brain is the central control hub of the whole body. Hence, the consequences of brain diseases can be lethal. Despite the progress in fundamental and clinical research, several key obstacles remain to be addressed. As an emerging science, aggregation-induced emission (AIE) has attracted great interest in the past few years owing to the overwhelming advantages of AIE luminogens (AIEgens), including their emission wavelength, quantum yield, spatial resolution, photosensitivity, photostability, signal-to-noise ratio, and biocompatibility. Herein, we provide a comprehensive summary of AIEgen applications in brain science, including health evaluation, disease detection, diagnosis, imaging, and therapeutics. The review has been summarized into five sections: i) Penetration of AIEgen-based nanomaterials across biological barriers; ii) Detection and diagnosis of brain diseases with AIEgen; iii) Bioimaging of the brain structure in health and disease with AIEgen; iv) Therapeutics for specific diseases in the brain using AIEgen; v) Future outlooks surrounding the applications of AIEgens in the brain. We hope that this review will promote a deeper understanding of the use of AIEgens in the neuroscience community and inspire additional research aimed at improving the current situation in the clinic. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) dots and nanoparticles have been widely applied in biological research recently due to their high brightness, large Stokes' shift, good photo-stability and excellent biocompatibility. However, most AIE dots contain amorphous features. In these cases, although the intramolecular motions can be restricted to some degree, amorphous AIE nanoparticles still suffer from loose molecular packing, leading to the limited brightness. To solve this problem and further restrict intramolecular motion, nano-crystallization has been recently reported to produce highly emissive AIE nanocrystals (NCs), which display great potential for biological applications. Although there have been some reviews on AIE dots in recent years, research on AIE NCs has not been reviewed yet. Based on these considerations, the recent progress on AIE NCs, including their working mechanism, materials, preparation, characterization and also applications, have been summarized in this work, thus, providing a full picture and deep understanding of AIE NCs. This review also aims to offer guidelines to develop high-performance AIE NCs for material science and biological applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A two-photon photodynamic photosensitizer with mitochondrion-targeting and AIE characteristics was prepared. • The integration of Ir make 50 times enhancement of ROS production compared to its counterpart molecule. • TPABP-Ir@BSA NPs exhibits satisfactory biosafety. • A 90% tumor suppression was achieved by type-I&II synergetic photochemical reactions under hypoxic environment. In recent years, two-photon photodynamic therapy (TP-PDT) has received extensive attention in cancer treatment owing to its unique advantages of deep tissue penetration and high spatial–temporal controls. However, the high oxygen dependency of photosensitizers still remained as the major obstacle which undermined its overall therapeutic efficacy, especially in hypoxic-tolerant tumors. Exploration of new TP-PDT strategy with less-oxygen-dependency and subcellular organelle-targeting ability is an appealing yet seriously challenging task. In this work, a mitochondrion-targeting TP-PDT protocol based on type-I PSs with aggregation-induced emission (AIE) characteristics is proposed for the first time. Of the two synthesized AIE-active PSs, TPABP-Ir is demonstrated superior reactive oxygen species (ROS) production (both type I&II) owing to the doping of Ir(III). After encapsulation into bovine serum albumin (BSA) matrix, TPABP-Ir@BSA nanoparticles (Ir-NPs) are capable of realizing mitochondrion-targeting, high ROS production, and suppression of tumor growth under 880 nm femtosecond laser excitation. This study provides a novel treatment strategy which maximizes the PDT efficacy and offers a conceptual but practical paradigm for cancer treatment in translational nanomedicine. [ABSTRACT FROM AUTHOR]