AIE-based luminescence probes for metal ion detection

Wavelength specific aggregation induced emission in aqueous media permits selective detection of Ag+ and Hg2+ ions

A new 1,8-naphthalimide derivative (probe 1) adopts V-shaped structure, emits fluorescence and displays the Mie effect and aggregation-induced emission (AIE). Selective interactions of thiophilic Ag+ and Hg2+ ions (10 µM) with 1 (10 µM) resulted in AIEs at 499 and 521 nm, respectively. Both Ag+ and Hg2+ induce the formation of 1:2 complexes with 1, leading to the formation of AIE active aggregates with an average size of 423 and 198 nm, respectively. The formation of crystalline needles with Ag+ and spherical aggregates with Hg2+ results in wavelength specific AIE that permits the naked-eye and fluorometric detection of Ag+ and Hg2+ ions. Probe 1 shows excellent selectivity toward Ag+ and Hg2+ among various metal ions, therefore, 1 is suitable for the selective and quantitative detection of Ag+ and Hg2+ ions. Job plots are used for the determination of the stoichiometry of the complexes formed. It is evident from the fluorescence images of probe 1 in Rhizoctonia oryzae mycelia cells that they can be employed as potential candidates for in-vitro bioimaging.

Redox interference-free bimodal paraoxon sensing enabled by an aggregation-induced emission nanozyme catalytically hydrolyzing phosphoesters specifically

In view of the current serious situation of organophosphorus pesticides (OPs) residue contamination, developing rapid and accurate OPs sensors is a matter of urgency. Redox-nanozyme based colorimetric sensors have been widely researched and utilized in OPs residue determination, but overcoming the interference of external redox substances and the effect of single-signal modes on detection performance is still a challenge. Here we fabricated a Zr-based metal-organic framework (MOF) featuring specific phosphatase-like activity and strong aggregation-induced emission (AIE) fluorescence for redox interference-free bimodal pesticide sensing. In the MOF, the activity-tunable Zr4+ node offered high hydrolytic activity and affinity toward P-O containing substrates, and the rigid framework structure effectively enhanced the fluorescence emission of the ligand 1,1,2,2-tetra(4-carboxylphenyl)ethylene. The developed AIEzyme could efficiently catalyze the hydrolysis of paraoxon to yellow p-nitrophenol, which further reduced the intrinsic AIE fluorescence of AIEzyme through internal filtration effect. Thereby, a natural enzyme-free dual-mode colorimetric/fluorescence approach was established for paraoxon detection with no interference from redox substances, and a smartphone-assisted portable platform was further developed to enable the facile, rapid, and high-performance sensing of the pesticide in complex practical matrices.

Intracellularly manipulable aggregation of the aggregation-induced emission luminogens

Biophotonics has seen significant advancements with the development of optical imaging techniques facilitating the noninvasive detection of biologically relevant species. Aggregation-induced emission (AIE) materials have emerged as a novel class of luminogens exhibiting enhanced luminescence or photodynamic efficiency in the aggregated state, making them ideal for biomedical applications. The intracellularly controlled aggregation of aggregate-induced emission luminogens (AIEgens) enables high-resolution imaging of intracellular targets and diagnosis of related diseases, and enables disease therapy by exploiting the novel properties of aggregates. This review provides an in-depth analysis of the strategies employed to modulate the aggregation of AIEgens, focusing on the importance of molecular modifications to improve hydrophilicity and achieve precise control over the intercellular aggregation of AIEgens. Furthermore, the representative applications of AIEgens in bioimaging, such as enzyme activity monitoring, protein tracking, organelle function monitoring, and in vivo tumor-specific therapeutics, are reviewed. Additionally, we outline the challenges and future opportunities for AIE research, emphasizing the importance of the strategies for realizing the precisely controllable aggregation of AIEgens inside cells and the need for extending AIEgens' absorption and emission wavelengths. This review aims to elucidate the rational development of responsive AIEgens for advanced biomedical applications.

Optical detection strategies for Ni(II) ion using metal-organic chemosensors: from molecular design to environmental applications

Nickel is an important element utilized in various industrial/metallurgical processes, such as surgical and dental prostheses, Ni-Cd batteries, paint pigments, electroplating, ceramics, computer magnetic tapes, catalysis, and alloy manufacturing. However, its extensive use and associated waste production have led to increased nickel pollution in soils and water bodies, which adversely affects human health, animals and plants. This issue has prompted researchers to develop various optical probes, hereafter luminescent/colorimetric sensors, for the facile, sensitive and selective detection of nickel, particularly in biological and environmental contexts. In recent years, numerous functionalized chemosensors have been reported for imaging Ni2+, both in vivo and in vitro. In this context, metal-based receptors offer clear advantages over conventional organic sensors (viz., organic ligands, polymers, and membranes) in terms of cost, durability, stability, water solubility, recyclability, chemical flexibility and scope. This review highlights recent advancements in the design and fabrication of hybrid receptors (i.e., metal complexes and MOFs) for the specific detection of Ni2+ ions in complex environmental and biological mixtures.

Chitosan based fluorescent probe with AIE property for detection of Fe3+ and bacteria

Fluorescent probe with aggregation-induced emission (AIE) property has been widely used because of the advantages of high sensitivity, good selectivity and non-destructive testing. The development of fluorescent probe with good biocompatibility, photostability and biodegradability is of great significance in biomedicine and environmental detection. Herein, a novel type of fluorophore CS-TPE for detection of Fe3+ and bacteria was prepared by the Schiff base reaction of chitosan (CS) and 4-(1,2,2-triphenylethenyl) benzaldehyde (TPE-CHO). The fluorescence response mechanism of CS-TPE system was investigated by various characterization techniques. CS-TPE had an obvious AIE behavior with strong blue-green emissions at 473 nm and reaches the highest photoluminescence (PL) emission in 90 % H2O/ethanol mixtures. CS-TPE fluorescent probe exhibited sensitive quenching response to Fe3+, which can be used as a biosensor for detecting the concentration of Fe3+ with short response time (5 min), low detection limit (0.998 μM) and wide detection range (10-300 μM). Meanwhile, CS-TPE exhibited good antibacterial performance for S. aureus and E. coli. It is expected to realize the real-time fluorescence monitoring of metal ion detection and antibacterial process.

Solid-state nanochannels based on electro-optical dual signals for detection of analytes

The sensitive detection of analytes of different sizes is crucial significance for environmental protection, food safety and medical diagnostics. The confined space of nanochannels provides a location closest to the molecular reaction behaviors in real systems, thereby opening new opportunities for the precise detection of analytes. However, due to the susceptibility to external interference on the confined space of nanochannels, the high sensitivity nature of the current signals through the nanochannels is more troubling for the detection reliability. Combining highly sensitive optical signals with the sensitive current signals of solid-state nanochannels establishes a nanochannel detection platform based on electro-optical dual signals, potentially offering more sensitive, specific, and accuracy detection of analytes. This review summarizes the last five years of applications of solid-state nanochannels based on electro-optical dual signals in analytes detection. Firstly, the detection principles of solid-state nanochannels and the construction strategies of nanochannel electro-optical sensing platforms are discussed. Subsequently, the review comprehensively outlines the applications involving nanochannels with electrical signals combined with fluorescence signals, electrical signals combined with surface-enhanced Raman spectroscopy signals, and electrical signals combined with other optical signals in analyte detection. Additionally, the perspectives and difficulties of nanochannels are investigated on the basis of electro-optical dual signals.

Hydrazide Schiff base Compound Containing Triphenylphosphonium Units for Fluorescence Sensing of Al3+ and its real Sample Applications

Al3+ excess in the body can cause many diseases. The development of chemosensors for the detection of Al3+ is therefore highly desirable. A hydrazide Schiff base compound containing triphenylphosphonium units (ER) was prepared and used as fluorescence turn-on sensor for the sensing of Al3+. Detection of Al3+ among various metals has been achieved successfully through the formation of Al3+-ligand coordination complexes. To detect Al3+, the "turn on" property of the fluorogenic chemosensor was investigated. Fluorescence sensing studies were carried out in CH3OH-Water (v/v, 9/1, pH 7.0) at λem = 528 nm. The LOD for sensing of Al3+ was found to be 0.129 µM. Using Job's graph, the stoichiometric ratio of ER- Al3+ was determined to be 1:1. The binding constant was determined to be 1.7 × 107 M-1 between Al3 + and the chemosensor ER. Finally, the determination of Al3+ in real herbal teas was carried out by using the sensing function of the chemosensor ER.

Aggregation-Induced Emission Luminogen: Role in Biopsy for Precision Medicine

Biopsy, including tissue and liquid biopsy, offers comprehensive and real-time physiological and pathological information for disease detection, diagnosis, and monitoring. Fluorescent probes are frequently selected to obtain adequate information on pathological processes in a rapid and minimally invasive manner based on their advantages for biopsy. However, conventional fluorescent probes have been found to show aggregation-caused quenching (ACQ) properties, impeding greater progresses in this area. Since the discovery of aggregation-induced emission luminogen (AIEgen) have promoted rapid advancements in molecular bionanomaterials owing to their unique properties, including high quantum yield (QY) and signal-to-noise ratio (SNR), etc. This review seeks to present the latest advances in AIEgen-based biofluorescent probes for biopsy in real or artificial samples, and also the key properties of these AIE probes. This review is divided into: (i) tissue biopsy based on smart AIEgens, (ii) blood sample biopsy based on smart AIEgens, (iii) urine sample biopsy based on smart AIEgens, (iv) saliva sample biopsy based on smart AIEgens, (v) biopsy of other liquid samples based on smart AIEgens, and (vi) perspectives and conclusion. This review could provide additional guidance to motivate interest and bolster more innovative ideas for further exploring the applications of various smart AIEgens in precision medicine.

Polymerization-induced emission and selective detection to Fe3+/ Fe2+ of triazine-containing polyureas

In this study, four polyureas with triazine moiety (PUAs) were successfully synthesized through the polymerization of triazine-containing diamine and diisocyanate. The intramolecular aggregation of triazine rings and urea groups along the macromolecular backbone gives PUAs a significant polymerization-induced emission (PIE). Among the four PUAs, PUA-LP shows a significant fluorescent emission at 450 nm, compared to non/weak fluorescent 2,4-diamino-6-phenyl-1,3,5-triazine and L-Lysine diisocyanate ethyl ester monomers. Additionally, the external factors such as solution concentration, excitation wavelength, and precipitants also play a crucial role in the fluorescence of PUAs. As expected, PUA-LP can selectively recognize and detect Fe3+/Fe2+ ions even in the presence of 12 other metal ions and 10 anions. The limit of detection of PUA-LP to Fe3+/Fe2+ is as low as 1.02 μM (0.06 mg/L) and 0.86 μM (0.05 mg/L), respectively, and far below 0.3 mg/L of the allowable national standard for drinking water by WHO. Furthermore, the quenching mechanism of Fe3+/Fe2+ to PUA-LP is attributed to static quenching caused by the coordination of Fe3+/Fe2+ ions with a coordination ratio of 2:1. Based on PIE, the fluorescent PUA-LP was made into an observable and portable testing paper for detecting Fe3+/Fe2+ ions. Finally, we measured the recovery rate of the actual tap water samples and compared the performance of PIE-active PUA-LP with the other reported fluorescent probes to Fe3+/Fe2+ ions.

Aggregation-induced emission luminescence for angiography and atherosclerotic diagnosis

Optical imaging technology has become increasingly recognized for its utility in diagnosing atherosclerosis thanks to advantages such as high spatial resolution, rapid data acquisition, lack of radiation exposure, cost-effectiveness, minimal invasiveness, and limited side effects. However, traditional luminogens employed in optical diagnostics are often troubled by aggregation-caused quenching (ACQ) effect, causing diagnostic errors in vivo. Since Professor Tang discovered the aggregation-induced emission (AIE) phenomenon, AIE luminogens (AIEgens) have been rapidly developing and are considered as the next-generation fluorescent contrast agents for angiography and atherosclerotic diagnosis. This mini review will outline the use of AIEgens in angiography and the diagnosis of atherosclerosis, exploring different imaging models, including second near-infrared, two/multi-photon, and photoacoustic imaging, and will provide a forward-looking perspective on their potential in atherosclerotic diagnosis.

Expanding Our Horizons: AIE Materials in Bacterial Research

Bacteria share a longstanding and complex relationship with humans, playing a role in protecting gut health and sustaining the ecosystem to cause infectious diseases and antibiotic resistance. Luminogenic materials that share aggregation-induced emission (AIE) characteristics have emerged as a versatile toolbox for bacterial studies through fluorescence visualization. Numerous research efforts highlight the superiority of AIE materials in this field. Recent advances in AIE materials in bacterial studies are categorized into four areas: understanding bacterial interactions, antibacterial strategies, diverse applications, and synergistic applications with bacteria. Initial research focuses on visualizing the unseen bacteria and progresses into developing strategies involving electrostatic interactions, amphiphilic AIE luminogens (AIEgens), and various AIE materials to enhance bacterial affinity. Recent progress in antibacterial strategies includes using photodynamic and photothermal therapies, bacterial toxicity studies, and combined therapies. Diverse applications from environmental disinfection to disease treatment, utilizing AIE materials in antibacterial coatings, bacterial sensors, wound healing materials, etc., are also provided. Finally, synergistic applications combining AIE materials with bacteria to achieve enhanced outcomes are explored. This review summarizes the developmental trend of AIE materials in bacterial studies and is expected to provide future research directions in advancing bacterial methodologies.

Exploring Cyclopentannulation as an Effective Synthetic Tool to Design Polycyclic Aromatic Hydrocarbon AIEgens for Bioimaging

Synthesis of various polycyclic aromatic hydrocarbons (PAHs) from a palladium-catalyzed [3 + 2] cyclocondensation reaction is reported herein. The design strategy consisted of reacting the sterically hindered 1,2-bis(3,5-ditert-butylphenyl)acetylene 2 with myriad brominated anthracene and pyrene surrogates, resulting in the formation of target molecules MCP1-2 and DCP1-3, which exhibited excellent solubility in commonly used organic solvents and unveiled prominent aggregation-induced emission (AIE) characteristics in tetrahydrofuran and water solvent mixtures. Calculations using density functional theory (DFT) were utilized to validate both the contorted structures of the target molecules and their electronic conjugation featuring HOMO-LUMO band gaps (ΔE) in the range of ∼2.88 to 2.97 eV for the monocylopentannulated PAHs MCP1-2, and between ∼2.23 to 2.41 eV for the dicyclopentannulated PAHs DCP1-3. Furthermore, the biomedical features of DCP2 were investigated in cell-imaging experiments employing the RAW 264.7 macrophage cell line as a model system showing a high biocompatibility for DCP2, thus paving the way for its potential application in bioimaging. These findings underscore the significance of the target compounds as prominent AIEgens with exceptional photophysical properties and biocompatibility, therefore promoting them as valuable tools for bioimaging applications.

Bi-component sensing platform for the detection of Cd2+, Fe2+and Fe3+ ions

The ability of N-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)isonicotinamide (naphydrazide) or 2,6-pyridinedicarboxylic acid (2,6-H2pdc) individually or as a bi-component system in distinguishing and detecting Fe3+ or Fe2+ and Cd2+ ions was investigated. The use of these molecules as single or bi-component analytes in absorption or emission spectroscopy studies showed that under specific conditions each had their own merits for specific purposes. UV-visible spectroscopic studies of 2,6-H2pdc for assessing the interactions with ferrous and ferric ions showed characteristic distinctions. The detection limit for Fe3+ analysed through UV-visible spectroscopy using naphydrazide was 0.46 μM, whereas it was 1.28 μM using 2,6-H2pdc. Naphydrazide together with Fe3+ allowed distinguishing Cd2+ ions from Zn2+ and Fe2+ ions. The bi-component system was useful for the selective detection of Cd2+ ions using fluorescence spectroscopy, with a detection limit for Cd2+ ions of 18.31 μM. The presence of Fe2+ and Cd2+ ions in a solution of the bi-component had resulted white-light emission. An analogous compound N,N'-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthroline-2,7(1H,3H,6H,8H)-diyl)diisonicotinamide (binaphydrazide) was found unsuitable for such detections. Two 2,6-pyridinedicarboxylate Fe3+ complexes possessing protonated naphydrazide or binaphydrazide were prepared and characterised. These complexes were also found unsuitable for the detection of the said ions in solution. Electrochemical studies with the bi-component system showed that cyclic voltammograms could distinguish Fe3+ or Fe2+ from Cd2+ ions.

A novel red-to-near-infrared AIE fluorescent probe for detection of Hg2+ with large Stokes shift in plant and living cells

Due to the highly toxic nature of mercury ions to living organisms, accurately detecting Hg2+ in water samples and biological systems is of great significance. In this study, we designed and synthesized a novel red-to-near-infrared Aggregation-Induced Emission (AIE) fluorescent probe (named as DS) based Fluorene derivatives on specifically for Hg2+ detection. Probe DS can visually identify Hg2+ through an red-to-near-infrared fluorescence enhancement change, characterized by a large Stokes shift (130 nm) and AIE feature. This probe offers a fast response, high selectivity and sensitivity. The Hg2+-induced deprotection reaction of the thioketal mechanism was thoroughly investigated using nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS) and density functional theory (DFT) calculation. Additionly, dynamic light scattering (DLS) results indicated that the aggregation states changes of the molecular play a crucial role in the AIE fluorescence response of probe DS toward Hg2+. The red-to-near-infrared response with AIE feature not only avoids the interference of auto-fluorescence signals in complex environments, but also reduces the fluorescence quenching caused by probe molecular aggregation. This makes probe DS highly suitable for high-quality imaging detection of Hg2+ in aqueous environments. Furthermore, probe DS demonstrates the capability for visual fluorescence detection of Hg2+ concentrations in water sample, plant roots and living cells.

Aggregation-Induced Emission Phosphorescence Featured Au-Ag Coordination Polymer with a Diphosphine N-Heterocyclic Carbene Ligand for Highly Sensitive Detection of Cr(VI)

Luminescent materials with aggregation-induced emission (AIE) characteristics have been recognized as highly selective and sensitive probes for the detection of toxic metal ions in recent years. In this paper, a Au-Ag cluster-based coordination polymer [Au3Ag3(L)2(CN)6(H2O)2]n [1, L = 1,3-bis((diphenylphosphanyl)methyl)-4,5-dihydro-imidazolylidene] was prepared by in situ generation of the diphosphine N-heterocyclic carbene (PCNHCP)-type ligand L in the presence of the corresponding metal salts. Compound 1 exhibited 530 nm phosphorescence under 380 nm excitation with a QY of 6.30% and a lifetime (τ) of 7.14 μs in the solid state. 1 showed good AIE behavior in the mixture of MeOH/H2O while the best aggregation state (fwater = 90%, QY = 6.79%, τ = 6.70 μs) exhibited selective and sensitive emission quenching toward Cr(VI) ions. Ultralow detection limits of 9.7 ppb (w/w) for Cr2O72- and 17.9 ppb (w/w) for CrO42- were achieved.

Turn-on detection of Al3+ ions using quinoline-based tripodal probe: mechanistic investigation and live cell imaging applications

In this study, an easily synthesizable Schiff base probe TQSB having a quinoline fluorophore is demonstrated as a fluorescent and colorimetric turn-on sensor for Al3+ ions in a semi-aqueous medium (CH3CN/water; 4 : 1; v/v). Absorption, emission and colorimetric studies clearly indicated that TQSB exhibited a high selectivity toward Al3+, as observed from its excellent binding constant (Kb = 3.8 × 106 M-1) and detection limit (7.0 nM) values. TQSB alone was almost non-fluorescent in nature; however, addition of Al3+ induced intense fluorescence at 414 nm most probably due to combined CHEF (chelation-enhanced fluorescence) and restricted PET effects. The sensing mechanism was established via Job's plot, NMR spectroscopy, ESI-mass spectrometry, and density functional theory (DFT) analyses. Furthermore, to evaluate the applied potential of probe TQSB, its sensing ability was studied in real samples such as soil samples and Al3+-containing Digene gastric tablets as well as on low-cost filter paper strips. Fluorescence microscopy imaging experiments further revealed that TQSB can be used as an effective probe to detect intracellular Al3+ in live cells with no cytotoxicity.

One-to-Nine Single Spectroscopic Intelligent Probe for Risk Assessment of Multiple Metals in Drinking Water

26% of the world's population lacks access to clean drinking water; clean water and sanitation are major global challenges highlighted by the UN Sustainable Development Goals, indicating water security in public water systems is at stake today. Water monitoring using precise instruments by skilled operators is one of the most promising solutions. Despite decades of research, the professionalism-convenience trade-off when monitoring ubiquitous metal ions remains the major challenge for public water safety. Thus, to overcome these disadvantages, an easy-to-use and highly sensitive visual method is desirable. Herein, an innovative strategy for one-to-nine metal detection is proposed, in which a novel thiourea spectroscopic probe with high 9-metal affinity is synthesized, acting as "one", and is detected based on the 9 metal-thiourea complexes within portable spectrometers in the public water field; this is accomplished by nonspecialized personnel as is also required. During the processing of multimetal analysis, issues arise due to signal overlap and reproducibility problems, leading to constrained sensitivity. In this innovative endeavor, machine learning (ML) algorithms were employed to extract key features from the composite spectral signature, addressing multipeak overlap, and completing the detection within 30-300 s, thus achieving a detection limit of 0.01 mg/L and meeting established conventional water quality standards. This method provides a convenient approach for public drinking water safety testing.

State-of-the-art of lignin-derived carbon nanodots: Preparation, properties, and applications

Lignin-derived carbon nanodots (LCNs) are nanometer-scale carbon spheres fabricated from naturally abundant lignin. Owing to rich and highly heritable graphene like π-π conjugated structure of lignin, to fabricate LCNs from it not only endows LCNs with on-demand tunable size and optical features, but also further broadens the green and chemical engineering of carbon nanodots. Recently, they have become increasingly popular in sensing, bioimaging, catalysis, anti-counterfeiting, energy storage/conversion, and others. Despite the enormous research efforts put into the ongoing development of lignin value-added utilization, few commercial LCNs are available. To have a deeper understanding of this issue, critical impacts on the preparation, properties, and applications of state-of-the-art LCNs are carefully reviewed and discussed. A concise analysis of their unique advantages, limitations for specific applications, and current challenges and outlook is conducted. We hope that this review will stimulate further advances in the functional material-oriented production of lignin.

The complexometric behavior of selected aroyl-S,N-ketene acetals shows that they are more than AIEgens

Using the established synthetic methods, aroyl-S,N-ketene acetals and subsequent bi- and multichromophores can be readily synthesized. Aside from pronounced AIE (aggregation induced emission) properties, these selected examples possess distinct complexometric behavior for various metals purely based on the underlying structural motifs. This affects the fluorescence properties of the materials which can be readily exploited for metal ion detection and for the formation of different metal-aroyl-S,N-ketene acetal complexes that were confirmed by Job plot analysis. In particular, gold(I), iron(III), and ruthenium (III) ions reveal complexation enhanced or quenched emission. For most dyes, weakly coodinating complexes were observed, only in case of a phenanthroline aroyl-S,N-ketene acetal multichromophore, measurements indicate the formation of a strongly coordinating complex. For this multichromophore, the complexation results in a loss of fluorescence intensity whereas for dimethylamino-aroyl-S,N-ketene acetals and bipyridine bichromophores, the observed quantum yield is nearly tripled upon complexation. Even if no stable complexes are formed, changes in absorption and emission properties allow for a simple ion detection.

Tetrakispyrazolylethene: Protonation-Induced Emission

Tetrakispyrazolylethene (1) was synthesized from pyrazole and hexachloroethane through a one-step substitution reaction. The increase of emission was detected both in solid and aqueous THF solution, compared with that in anhydrous THF. While the former originates from the crystal packing, the latter is attributed to the protonation-induced emission, independent of aggregation, based on the optical measurement under varying concentrations and particle-size distribution analysis.

Rational design of a rapidly responsive and highly selective fluorescent probe for SO2 derivatives detection and imaging

Sulfur dioxide (SO2) is emerging as a double-edged molecule, while plays vital roles in food and biological system. However, the fast, highly sensitive, and versatile fluorescent probe still remains a tough challenge among current reports. Herein, we developed a novel aggregation-induced emission (AIE) fluorescent probe TPE-PN for specifically sensing SO2 derivatives with high sensitivity (150 nmol/L) and rapid response time (10 s) based on intramolecular charge transfer (ICT) mechanism. And the fluorescence at 575 nm decreased tremendously with 31-fold after the probe was treated with HSO3-. Employing the probe, the accurate analysis of HSO3- was successfully realized in food samples, cells, plant tissues, and zebrafishes. Furthermore, we successfully demonstrate the eruption of SO2 derivatives within plant during drought and salt stress processes. Therefore, probe TPE-PN illustrates significant potential for applications in food analysis and monitoring of SO2 derivatives levels in biological systems under stress conditions.

Red Fluorescent Molecule with Aggregation-Induced Emission Based on Dehydroabietic Acid Diarylamine for Bioimaging

In this paper, molecules with AIE red light properties were designed by coupling dehydroabietic acid diarylamine and 2,3-diphenylfumaronitrile, which were designated 2DTPA-CN and 2TPA-CN. The emission wavelengths were 683 nm and 701 nm, respectively. The 2DTPA-CN and 2TPA-CN showed typical AIE characteristics with large Stokes shifts of 7.4 × 104 cm-1 and 6.7 × 104 cm-1, respectively. The obvious solvatochromism and electron cloud distributions of HOMO/LUMO in the ground and excited states both reveal the intramolecular charge transfer (ICT) effect. The 2DTPA-CN, boasting exceptional biocompatibility, was successfully prepared into nanoparticles (NPs), which were applied to tumor cell imaging, showing good bioimaging effects both in vitro imaging in live cells and in vivo imaging in live mice. The results demonstrated that it possesses significant potential as an effective bioimaging reagent for the detection of tumor cells. Furthermore, the incorporation of 2,3-diphenylfumaronitrile moieties to dehydroabietic acid diarylamine emerged as a proficient approach to broaden the emission wavelengths of rosin-based fluorescent materials.

Grind, shine and detect: mechanochemical synthesis of AIE-active polyaromatic amide and its application as molecular receptor of monovalent anions or nucleotides

A mechanochemical synthesis of novel polyaromatic amide consisting of 1,3,5-triphenylbenzene and 1,1',2,2'-tetraphenylethylene skeletons has been established. The designed mechanochemical approach using readily available and low-cost equipment allowed a twofold increase in reaction yield, a 350-fold reduction in reaction time and a significant reduction in the use of harmful reactants in comparison to the solution synthesis method. The parameters of Green Chemistry were used to highlight the advantages of the developed synthesis method over the solution-based approach. The title compound was found to exhibit attractive optical properties related to the Aggregation-induced emission (AIE) behaviour. Taking the advantage of AIE-active properties of the synthesized polyaromatic amide, its application as effective and versatile molecular receptor towards detection of monovalent anions, as well as bio-relevant anions - nucleotides, has been demonstrated. The values of the binding constants were at the satisfactory level of 104, the detection limit values were low and ranged from 0.2 μM to 19.9 μM.

Recent advances in super-resolution optical imaging based on aggregation-induced emission

Super-resolution imaging has rapidly emerged as an optical microscopy technique, offering advantages of high optical resolution over the past two decades; achieving improved imaging resolution requires significant efforts in developing super-resolution imaging agents characterized by high brightness, high contrast and high sensitivity to fluorescence switching. Apart from technical requirements in optical systems and algorithms, super-resolution imaging relies on fluorescent dyes with special photophysical or photochemical properties. The concept of aggregation-induced emission (AIE) was proposed in 2001, coinciding with unprecedented advancements and innovations in super-resolution imaging technology. AIE probes offer many advantages, including high brightness in the aggregated state, low background signal, a larger Stokes shift, ultra-high photostability, and excellent biocompatibility, making them highly promising for applications in super-resolution imaging. In this review, we summarize the progress in implementation methods and provide insights into the mechanism of AIE-based super-resolution imaging, including fluorescence switching resulting from photochemically-converted aggregation-induced emission, electrostatically controlled aggregation-induced emission and specific binding-regulated aggregation-induced emission. Particularly, the aggregation-induced emission principle has been proposed to achieve spontaneous fluorescence switching, expanding the selection and application scenarios of super-resolution imaging probes. By combining the aggregation-induced emission principle and specific molecular design, we offer some comprehensive insights to facilitate the applications of AIEgens (AIE-active molecules) in super-resolution imaging.

Schiff base fluorescent sensor with aggregation induced emission characteristics for the sensitive and specific Fe3+ detection

An aggregation induced emission based compound ((E)-4-((2-hydroxy-5-methoxybenzylidene)amino)benzoic acid) was synthesized through facile Schiff base condensation and characterized by various spectral techniques. The as-prepared compound represented a typical aggregation induced emission behavior in aqueous solution and exploited as a turn-off fluorescent sensor for Fe3+ detection in THF-H2O system (3:7, v/v) with high sensitivity and selectivity. The mechanism of the fluorescence quenching was intensively studied, which was attributed to both dynamic quenching and inner filter effect. The fluorescence probe displayed a highly broad dynamic response range (0.5-500 μM) for selective detection of Fe3+ with a limit of detection of 0.079 μM. The proposed method was successfully employed for detection and quantification of Fe3+ in human urine samples and proved to have potential for practical applications in biological field.

AIE luminogen labeled polymeric micelles for biological imaging and chemotherapy

In this study, an amphiphilic polymer FA-CS-DBA-CHO with aggregation-induced emission (AIE) feature was prepared by introducing 4-(diphenylamino)benzaldehyde derivative (DBA-CHO), imine bond and folic acid (FA) to the molecular structure of chitosan (CS). The amphiphilicity drove the polymer to self-assemble into micelles, and paclitaxel (PTX) could be solubilized in the hydrophobic core. Due to the excellent AIE effect, FA-CS-DBA-CHO exhibited strong cellular imaging capability. The pH-sensitive imine bond in the polymer allowed for accurate drug release in acidic environment. Both in vitro and in vivo studies demonstrated that the PTX-loaded FA-CS-DBA-CHO micelles could significantly inhibit the growth of tumor cells but without any notable toxicity. This micellar system was excellent carrier for bioimaging and chemotherapeutic drug delivery.

AIE-based ratiometric fluorescent probe for mercury ion, medium-dependent fluorescence color change and optimized sensitivity in solid state

A new AIE-based luminogen TPES, as a ratiometric fluorescence probe for mercury(II) was readily synthesized. The probe combined the advantages of the outstanding specificity of Hg2+-triggered deprotection reaction of thioketal and the brilliant emission of AIEgens in aggregated state. Once encountered aqueous Hg2+, fluorescent color of TPES in THF-H2O (fw = 98%) altered from blue to green rapidly, while other metal cations gave no interference to the probe. And the mechanism of this chemosensor was carefully verified by 1H NMR analysis, FTIR and MS spectra. As expected, TPES exhibits excellent selectivity and sensitivity towards Hg2+ in the solid state. When using filter paper as the solid medium, the fabricated test strips could signify Hg2+ ions with the LOD as 1 × 10-5 M (Hg2+ in aqueous solution), accompanied with a distinct emitting altered from blue to green. Furthermore, by changing the medium from filter paper to silica gel plate, a more significant fluorescence alteration from blue to yellow was achieved, and the LOD was further optimized to 1 × 10-6 M as discerned by naked-eye.

Enhancing or Quenching of a Mitochondria-Targeted AIEgens-Floxuridine Sensor by the Regulation of pH-Dependent Self-assembly, Efficient Recognition of Hg2+, and Stimulated Response of GSH

Biocompatible fluorescent probes have emerged as essential tools in life sciences for visualizing subcellular structures and detecting specific analytes. Herein, we report the synthesis and characterization of a novel fluorescent probe (TPE-FdU), incorporated with hydrophilic 2'-fluoro-substituted deoxyuridine and hydrophobic ethynyl tetraphenylethene moieties, which possessed typical aggregation-induced emission (AIE) behavior. In comparison to the TPE-FdU (pKa 7.68) treated in neutral conditions, it performed well at pH 4, exhibiting an enhanced 450 nm emission signal of approximately four times stronger. As the pH value was increased to 10, the fluorescence intensity was completely quenched. The TEM images of TPE-FdU in an acidic environment (nanospherical morphology, AIE enhance, pH = 4) and in a basic environment (microrods, fluorescence quenching, pH = 9) revealed that it was a pH-dependent self-assembled probe, which was also illustrated by the interpretation of the NMR spectrum. Furthermore, the TPE-FdU probe exhibited a specific response to trace Hg2+ ions. Interestingly, the quenched fluorescence of the TPE-FdU probe caused by Hg2+ can be recovered by the addition of GSH due to the formation of the Hg-S bond being released away. MTT assay and CLSM images demonstrated that TPE-FdU was nontoxic and selectively visualized in the intracellular mitochondria. These results contributed to the development of advanced fluorescent probes with diverse applications in cell imaging, environment protection, and biomedical research.

Illuminating the path: aggregation-induced emission for food contaminants detection

Food safety is a global concern that deeply affects human health. To ensure the profitability of the food industry and consumer safety, there is an urgent need to develop rapid, sensitive, accurate, and cost-effective detection methods for food contaminants. Recently, the Aggregation-Induced Emission (AIE) has been successfully used to detect food contaminants. AIEgens, fluorescent dyes that cause AIE, have several valuable properties including high quantum yields, photostability, and large Stokes shifts. This review provides a detailed introduction to the principles and advantages of AIE-triggered detection, followed by a focus on the past five years' applications of AIE in detecting various food contaminants including pesticides, veterinary drugs, mycotoxins, food additives, ions, pathogens, and biogenic amines. Each detection principle and component is comprehensively covered and explained. Moreover, the similarities and differences among different types of food contaminants are summarized, aiming to inspire future researchers. Finally, this review concludes with a discussion of the prospects for incorporating AIEgens more effectively into the detection of food contaminants.

Turn-on detection of Al3+ and Zn2+ ions by a NSN donor probe: reversibility, logic gates and DFT calculations

An efficient dual functional naphthalene-derived Schiff base NpSb probe has been synthesised and evaluated for its fluorescence and chromogenic response towards metal ions. The NpSb probe was capable of selectively recognising Al3+ and Zn2+ ions when they were excited at the same wavelength in an aqueous organic solvent system. Almost non-fluorescent NpSb displayed a 'turn-on' fluorescence response when treated with Zn2+ (λem = 416 nm) and Al3+ (λem = 469 nm) ions due to the chelation-enhanced fluorescence (CHEF) effect. The limit of detection (LoD) values for Al3+ and Zn2+ have been determined to be 38.0 nM and 43.0 nM, respectively. The binding constants for Al3+ and Zn2+ were found to be 1.18 × 106 M-1 and 3.5 × 105 M-1, respectively. The NpSb also acted as a colorimetric sensor for Al3+ as the colour of the probe's solution turned to pale green from colourless upon Al3+ addition. The binding mechanism between NpSb and Zn2+/Al3+ was supported by the ESI-MS, Job's plot, NMR, and DFT studies. The reversibility experiments were carried out with an F- ion and EDTA with the development of corresponding logic gates. Moreover, NpSb could be applied to detect Al3+ ions in real samples such as tap water, distilled water and soil samples.

An aggregation-induced emission sensor combined with UHPLC-Q-TOF/MS for fast identification of anticoagulant active ingredients from traditional Chinese medicine

Xuebijing injection (XBJ) has a good therapeutic effect on the patients with severe coronavirus disease, but the material basis of XBJ with the anticoagulant effect to improve the coagulopathy and thromboembolism is still unclear. Herein, we developed a new strategy based on aggregation-induced emission (AIE) for monitoring thrombin activity and screening thrombin inhibitors from XBJ. The molecule AIE603 and the thrombin substrate peptide S-2238 were formed into AIE nanoparticle (AIENP) which emitted notable fluorescence due to the restriction of intramolecular motions. In the presence of thrombin, AIENP was specifically hydrolyzed and AIE603 was released from AIENP, leading to the decrease of fluorescence intensity. Furthermore, AIENP was combined with ultra-high performance liquid chromatography-fraction collector (UHPLC-FC) and ultra-high performance liquid chromatography quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) for separation, preparation, screening and identification of the thrombin inhibitors from XBJ, a total of 58 chemical constituents were identified, among which 6 compounds possessed higher anticoagulant activity. Notably, the overall inhibition rate of the 6 mixed standards was equivalent to about 60% of the inhibition rate of XBJ. Therefore, this work provides a novel, cheap and simple method for monitoring thrombin activity and is promising to screen active substances from traditional Chinese medicines.

AIEgen orthopalladated hybrid polymers for efficient inactivation of the total coliforms in urban wastewater

Monitorable AIE polymers with a bioactive pattern are employed in advanced biomedical applications such as functional coatings, theranostic probes, and implants. After the global COVID-19 pandemic, interest in developing surfaces with superior antimicrobial, antiproliferative, and antiviral activities dramatically increased. Many formulations for biocide surfaces are based on hybrid organic/inorganic materials. Palladium (II) complexes display relevant activity against common bacteria, even higher when compared to their uncoordinated ligands. This article reports the design and synthesis of two series of orthopalladated polymers obtained by grafting a cyclopalladated fragment on two different O, N chelating Schiff base polymers. Different grafting percentages were examined and compared for each organic polymer. The fluorescence emission in the solid state was explored on organic matrixes and grafted polymers. DFT analysis provided a rationale for the role of the coordination core. The antibacterial response of the two series of hybrid polymers was tested against the total coliform group of untreated urban wastewater, revealing excellent inactivation ability.

Recent Progress of Activity-Based Fluorescent Probes for Imaging Leucine Aminopeptidase

Leucine aminopeptidase (LAP) is an important protease that can specifically hydrolyze Leucine residues. LAP occurs in microorganisms, plants, animals, and humans and is involved in a variety of physiological processes in the human body. In the physiological system, abnormal levels of LAP are associated with a variety of diseases and pathological processes, such as cancer and drug-induced liver injury; thus, LAP was chosen as the early biochemical marker for many physiological processes, including cancer. Considering the importance of LAP in physiological and pathological processes, it is critical that high-efficiency and dependable technology be developed to monitor LAP levels. Herein, we summarize the organic small molecule fluorescence/chemiluminescence probes used for LAP detection in recent years, which can image LAP in cancer, drug-induced liver injury (DILI), and bacteria. It can also reveal the role of LAP in tumors and differentiate the serum of cirrhotic, drug-induced liver injury and normal models.

A novel chromophore reaction-based pyrrolopyrrole aza-BODIPY fluorescent probe for H2S detection and its application in food spoilage

In this work, we developed an aggregation-induced emission enhancement (AIEE) active and NIR emissive pyrrolopyrrole aza-BODIPY (PPAB) polymer (P1) for H₂S detection for the first time. P1 showed obvious colorimetric change from green to yellow-green and ratiometric fluorescence "turn on" phenomenon with 167 nm blue-shift (from dark red to bright green). The sensing mechanism revealed a novel chromophore reaction between imine in PPAB core and H₂S was involved, leading to less conjugated product. It exhibited distinct advantages of good selectivity, high sensitivity, and low detection limit of 0.66 μM. The potential applicability of P1 for H₂S detection in the real samples (tap water, lake water and milk) was demonstrated. In addition, the solid sensor prepared by loading P1 on the PMMA film was successfully realized the visual detection of gaseous H₂S gas produced from egg spoilage. Therefore, this work provides a promising approach based on novel sensing mechanism for monitoring H₂S in complicated biological systems and practical food samples.

Recent Progress in the Rational Design of Biothiol-Responsive Fluorescent Probes

Biothiols such as cysteine, homocysteine, and glutathione play significant roles in important biological activities, and their abnormal concentrations have been found to be closely associated with certain diseases, making their detection a critical task. To this end, fluorescent probes have become increasingly popular due to their numerous advantages, including easy handling, desirable spatiotemporal resolution, high sensitivity, fast response, and favorable biocompatibility. As a result, intensive research has been conducted to create fluorescent probes for the detection and imaging of biothiols. This brief review summarizes recent advances in the field of biothiol-responsive fluorescent probes, with an emphasis on rational probe design, including the reaction mechanism, discriminating detection, reversible detection, and specific detection. Furthermore, the challenges and prospects of fluorescence probes for biothiols are also outlined.

Preparation of temperature-responsive nanomicelles with AIE property as fluorescence probe for detection of Fe3+ and Fe2

Temperature-responsive nanomicelles with aggregation induced emission (AIE) property were prepared by the host-guest complexation of ferrocene functionalized tetraphenyl (TPE-Fc) and β-cyclodextrin-poly (N-isopropylacrylamide) (β-CD-(PNIPAM)₇). The AIE chromophore TPE-Fc bound to the hydrophobic cavity of cyclodextrin serves as the core of micelles, and temperature sensitive PNIPAM serves as the shell to give the micelles good solubility. The size of the nanomicelles is about 100 nm. At the excitation wavelength of 340 nm, the strongest fluorescent emission peak was 421 nm. The introduction of cyclodextrin star polymer increased the fluorescence intensity of nanomicelles, thus improving the recognition of probe to Fe³⁺ and Fe²⁺. The fluorescent probe can quickly detect Fe³⁺ and Fe²⁺ in water within 5 min even in the presence of various interfering ions. The detection limits of Fe³⁺ and Fe²⁺ were 1.04 μM and 0.78 μM, respectively in the range of 10-90 μM. The formation of complex between the probe and Fe³⁺/Fe²⁺ was supported by Job's plot. The probe was successfully applied to the detection of Fe³⁺and Fe²⁺ in actual water sample with a good recovery. In addition, a possible sensing mechanism for the interaction of iron ions with amide bond groups of nanomicelles was proposed.

Activatable dual-functional molecular agents for imaging-guided cancer therapy

Theranostics has attracted great attention due to its ability to combine the real-time diagnosis of cancers with efficient treatment modalities. Activatable dual-functional molecular agents could be synthesized by covalently conjugating imaging agents, therapeutic agents, stimuli-responsive linkers and/or targeting molecules together. They could be selectively activated by overexpressed physiological stimuli or external triggers at the tumor sites to release imaging agents and cytotoxic drugs, thus offering many advantages for tumor imaging and therapy, such as a high signal-to-noise ratio, low systemic toxicity, and improved therapeutic effects. This review summarizes the recent advances of dual-functional molecular agents that respond to various physiological or external stimuli for cancer theranostics. The molecular designs, synthetic strategies, activatable mechanisms, and biomedical applications of these molecular agents are elaborated, followed by a brief discussion of the challenges and opportunities in this field.

Aggregation-Induced Emission Luminogen-Encapsulated Fluorescent Hydrogels Enable Rapid and Sensitive Quantitative Detection of Mercury Ions

Hg²⁺ contamination in sewage can accumulate in the human body through the food chains and cause health problems. Herein, a novel aggregation-induced emission luminogen (AIEgen)-encapsulated hydrogel probe for ultrasensitive detection of Hg²⁺ was developed by integrating hydrophobic AIEgens into hydrophilic hydrogels. The working mechanism of the multi-fluorophore AIEgens (TPE-RB) is based on the dark through-bond energy transfer strategy, by which the energy of the dark tetraphenylethene (TPE) derivative is completely transferred to the rhodamine-B derivative (RB), thus resulting in intense photoluminescent intensity. The spatial networks of the supporting hydrogels further provide fixing sites for the hydrophobic AIEgens to enlarge accessible reaction surface for hydrosoluble Hg²⁺, as well create a confined reaction space to facilitate the interaction between the AIEgens and the Hg²⁺. In addition, the abundant hydrogen bonds of hydrogels further promote the Hg²⁺ adsorption, which significantly improves the sensitivity. The integrated TPE-RB-encapsulated hydrogels (TR hydrogels) present excellent specificity, accuracy and precision in Hg²⁺ detection in real-world water samples, with a 4-fold higher sensitivity compared to that of pure AIEgen probes. The as-developed TR hydrogel-based chemosensor holds promising potential as a robust, fast and effective bifunctional platform for the sensitive detection of Hg²⁺.

A susceptible coordination hybrid based terbium sensibilization coupled ESIPT effects for pattern discrimination of analogues

Multianalyte detection and analogue discrimination are extremely valuable frontier areas for their wide applications in environmental, medical, clinical and industrial analyses. Nowadays, researchers rack their brains on how to develop excellent multianalyte chemosensors that have presented huge challenges in designing high-efficient fluorescent sensing materials and constructing high-throughput detection methods. In this paper, we propose a novel strategy to utilize the dual-emission fluorescent detection platform as a lab-on-a-molecule, arising from the disalicylaldehyde-coordinated hybrid H₂Q_j3/Tb based terbium sensibilization coupled excited-state intramolecular proton transfer effects. Using the statistical analysis (PCA and HCA) for sensing signals of three fluorescence channels (431, 543 and 583 nm), we demonstrate this elaborate chemosensor with multianalyte detection of three species (solvents, anions and cations) and pattern discrimination of analogues. As a result, the H₂Q_j3/Tb shows great lab-on-a-molecule characters for each set of species, resulting in the easier identification of many critical analytes (e.g., H₂O, NO₂^- and Fe³⁺) and discrimination of analogues. In addition, it is also proven to be able to provide reliable content determination for an analyte, especially the NO₂^- (LOD = 0.37 μM), and discrimination for mixed analogues. A combination of easy-to-implement preparation procedure and data analysis technique makes this work promising for not only designing similar lanthanide-based materials but also realizing more high-efficient multianalyte sensing systems towards various potential applications.

As Fiber Meets with AIE: Opening a Wonderland for Smart Flexible Materials

Aggregation-induced emission luminogens (AIEgens) have recently been developed at a tremendous pace in the area of organic luminescent materials by virtue of their superior properties. However, the practical applications of AIEgens still face the challenge of transforming AIEgens from molecules into materials. Till now, many AIEgens have been integrated into fiber, endowing the fiber with prominent fluorescence and/or photosensitizing capacities. AIEgens and fiber complement each other for making progress in flexible smart materials, in which the utilization of AIEgens creates new application possibilities for fiber, and the fiber provides an excellent carrier for AIEgens towards realizing the conversion from molecule to materials and an ideal platform to research the aggregate state of AIEgens in mesoscale and macroscale. This review begins with a brief summary of the recent advances related to some typical AIEgens with various functions and the technology for the fabrication of AIEgen-functionalized fiber. The most representative applications are then highlighted by focusing on energy conversion, personal protective equipment, biomedical, sensor, and fluorescence-related fields. Finally, the challenges, opportunities, and tendencies in future development are discussed in detail. This review hopes to inspire innovation in AIEgens and fiber from the view of mesoscale and macroscale.

Aggregation-Induced Emission-Active Nanostructures: Beyond Biomedical Applications

The discovery of aggregation-induced emission (AIE) phenomenon in 2001 has had a significant impact on materials development across different research disciplines. AIE-active materials have been widely exploited for various applications in optoelectronics, sensing, biomedical, and stimuli-responsive systems, etc. This is made possible by integrating AIE features with other fields of science and engineering, such as nanoscience and nanotechnology. AIE has been extensively employed, particularly for biomedical applications, such as biosensing, bioimaging, and theranostics. However, development of AIE-based nanotechnology for other applications is comparatively less, although there have been increasing research activities in recent years. Given the significance and potential of the marriage between AIE hallmark and nanotechnology in AIE-active materials development, this review article summarizes and showcases the latest research efforts in AIE-based nanomaterials, including nanomaterials synthesis and their nonbiomedical applications, such as sensing, optoelectronics, functional coatings, and stimuli-responsive systems. A perspective on the outlook of AIE-based nanostructured materials and relevant nanotechnology for nonbiomedical applications will be provided, giving an insight into how to design AIE-active nanostructures as well as their applications beyond the biomedical domain.

Aggregation-induced emission enhancement (AIEE) of tetrarhenium(I) metallacycles and their application as luminescent sensors for nitroaromatics and antibiotics

The self-assembly of tetrarhenium metallacycles [{Re(CO)₃}₂(μ-dhaq)(μ-N-N)]₂ (3a, N-N = 1,3-bis(1-butylbenzimidazol-2-yl)benzene; 3b, N-N = 1,3-bis(1-octylbenzimidazol-2-yl)benzene), (H₂-dhaq = 1,4-dihydroxy-9,10-anthraquinone) and [{Re(CO)₃}₂(μ-thaq)(μ-N-N)]₂ (4, N-N = 1,3-bis(1-butylbenzimidazol-2-yl)benzene), (H₂-thaq = 1,2,4-trihydroxy-9,10-anthraquinone) under solvothermal conditions is described. The metallacycles 3a,b and 4 underwent aggregation-induced emission enhancement (AIEE) in THF upon the incremental addition of water. TEM images revealed that metallacycle 3a in a 60% aqueous THF solution formed rectangular aggregates with a wide size distribution, while a 90% aqueous THF solution resulted in the formation of a mixture of nanorods and amorphous aggregates due to rapid and abrupt aggregation. UV-vis and emission spectral profiles supported the formation of nanoaggregates of metallacycles 3a,b and 4 upon the gradual addition of water to a THF solution containing metallacycles. Further studies indicated that these nanoaggregates were excellent probes for the sensitive and selective detection of nitro group containing picric acid (PA) derivatives as well as antibiotics.

Noncancerous disease-targeting AIEgens

Noncancerous diseases include a wide plethora of medical conditions beyond cancer and are a major cause of mortality around the world. Despite progresses in clinical research, many puzzles about these diseases remain unanswered, and new therapies are continuously being sought. The evolution of bio-nanomedicine has enabled huge advancements in biosensing, diagnosis, bioimaging, and therapeutics. The recent development of aggregation-induced emission luminogens (AIEgens) has provided an impetus to the field of molecular bionanomaterials. Following aggregation, AIEgens show strong emission, overcoming the problems associated with the aggregation-caused quenching (ACQ) effect. They also have other unique properties, including low background interferences, high signal-to-noise ratios, photostability, and excellent biocompatibility, along with activatable aggregation-enhanced theranostic effects, which help them achieve excellent therapeutic effects as an one-for-all multimodal theranostic platform. This review provides a comprehensive overview of the overall progresses in AIEgen-based nanoplatforms for the detection, diagnosis, bioimaging, and bioimaging-guided treatment of noncancerous diseases. In addition, it details future perspectives and the potential clinical applications of these AIEgens in noncancerous diseases are also proposed. This review hopes to motivate further interest in this topic and promote ideation for the further exploration of more advanced AIEgens in a broad range of biomedical and clinical applications in patients with noncancerous diseases.