Over the past three decades, a variety of complex structures mimicking intermetallic compounds have been discovered in soft matter systems. However, a complete understanding of the mechanisms that govern the self-assembly of these complex structures in aqueous solution is still lacking. Herein, we investigate the formation of mesoscale complex crystal structures with micelle packing of nonionic amphiphilic molecules in aqueous solutions using small-angle X-ray scattering (SAXS). The SAXS measurements revealed both unary-micelle and binary-micelles liquid crystalline phases, including face-centered cubic (FCC), body-centered cubic (BCC), Frank-Kasper (FK) σ, and FK A15 and NaZn₁₃, FK C14, and FK C15 phases, respectively, which arise from the interplay of composition, temperature, and time. Quantitative SAXS analyses with Le Bail refinements and electron density reconstruction indicated that EO hydration, the interfacial curvature of micelles, and micellar packing play important roles in the formation of mesoscale complex crystalline structures during the self-assembly process of the nonionic ternary system. This study is the first demonstration of binary mesoscale complex crystalline structures with quasispherical close packing in nonionic amphiphilic aqueous solution, offering broader insights for the self-assembly mechanism of the complex crystalline structures on soft materials.

The recovery of valuable transition metals from deactivated catalysts is crucial for alleviating the challenges of resource scarcity and environmental pollution. Guided by AI-powered big data analysis, we identified an important research gap in the sustainable recovery of early transition metals and proposed a solid-phase upcycling strategy to transform waste catalysts into highly valuable single-atom catalysts (SACs). This involves a heat-induced redispersion of metal aggregates into single atoms on the polycrystalline carbon nitride (PCN) support, producing highly active M₁-PCN SACs up to 20 wt% (M = Cu, Fe, Co, and Ni). Subsequent techno-economic analysis confirms a two-thirds reduction in production cost and greenhouse gas emissions compared to conventional hydrometallurgical and pyrometallurgical processes, thus paving a new path in the development of sustainable technologies for metal recovery.

To realize highly sensitive and specific sensing toward sarin, an Eu(III) based metal-organic framework (Eu-CTTB-MOF), encompassing a π-conjugated organic ligand H₄CTTB (4,4′,4″,4‴-(9H-carbazole-1,3,6,8-tetrayl)tetrabenzoic acid) was explored for ratiometric fluorescent sensing. An unprecedented specific recognition of nerve-agent sarin mimic diethyl chlorophosphate (DCP) in the presence of HCl interferent and a low limit of detection (LOD, 20.97 nM) were achieved. This excellent detection performance is driven by the dual hydrogen bonding and hydrophobic interaction between the CTTB organic ligand and DCP, which would cause a dramatic change in the molecular configuration of the CTTB ligand. Density functional theory (DFT) calculations further verify the recognition of DCP by Eu-CTTB-MOF could suppress the rotations of the aromatic rings in CTTB ligand, significantly reducing the nonradiative decay pathways and subsequently enhancing the fluorescent intensity of the CTTB ligand. Especially, the Eu-CTTB-MOF enables the immediate response to DCP vapor and excellent specificity towards DCP even in the presence of 18 types of interferents, including HCl vapor, structural analogs, and volatile organic solvent, and a gas detector with accurate detection of DCP in simulated scenarios, positioning the designed MOF as a promising sensing material for practical scenarios. We expect that the present sensing strategy will shine a light on the development of brand-new sensing materials for on-site detection applications.

Bioorthogonal cleavage chemistry (BCC) has been extensively applied to fluorescence-based imaging in cancer diagnostics. Its potential in chemiluminescence imaging is to be explored. In this study, a smart ruthenium (Ru)-catalyzed bioorthogonal activation chemiluminescence (BAC) probe is developed by integrating BCC with a phenoxy-adamantyl-1,2-dioxetane (PAD) for real-time in vivo imaging of thiol-containing metabolites, particularly hydrogen sulfide (H₂S), associated with thiol dysregulation in the tumor microenvironment. The BAC probe overcomes many limitations that existed in other chemiluminescence probes via a highly selective “Ru-locked” mechanism to achieve light-independent, thiol-triggered activation in the complex tumor microenvironment. This mechanism enables rapid activation (1 min), high sensitivity (LOD = 0.243 µM), and stable luminescence with a half-life of 18.5 h, as determined in vitro, across a broad emission range (400–800 nm). The probe also demonstrates enhanced selectivity for thiol-containing metabolites, particularly H₂S, and exhibits low toxicity both in vitro and in vivo. In a breast cancer mouse model, the probe successfully visualizes endogenous H₂S with high spatial precision, supporting its utility in tumor localization and image-guided surgery. In addition, the PAD scaffolds are developed via an efficient synthetic route, significantly lowering production costs (300- to 400-fold) and increasing yields from 40% to 95%. Furthermore, our BAC probe holds a broad potential for noninvasive diagnosis and real-time monitoring of thiol dysregulation and pathophysiological processes.

Ultrahigh signal-to-noise ratio (SNR) labeling enables precise visualization of biological structures in vivo. We boosted fluorogenicity in group-14-rhodamines by comprehensively manipulating their dynamics in physical (aggregate/monomer, K_A/M) and chemical (closed/open spirolactone, K_C/O) states. Fluorogenic rhodamines were designed by group 14 (C, Si, Ge) substituted bridging regions in xanthene with tuned dialkylation. We quantified the impact of alkylation with the hydrophobicity (logP) over a wide range and confirmed that SNR can be sharply improved, owing to the promoted nano-aggregation (K_A/M) with high logP. Integrating K_A/M with K_C/O mechanisms, unparalleled fluorogenicity was observed in group-14-rhodamines: HaloTag probe with dipentylsilyl exhibits remarkable fluorogenicity (>2000) in vitro, enabling no-wash and multicolor super-resolution stimulated emission depletion imaging of high SNR (>300) in vivo. Overexpression of α_vβ₃ was sensitively tracked in vivo by RGDyK-based fluorogenic SiR probe through tuned K_A/M. Our proposed strategy has significantly promoted the fluorogenicity of group 14 rhodamines as a general mechanism.

Realizing circularly polarized luminescence (CPL) with the same chiral direction by chiral luminogenic molecules under the identical conditions is unprecedented. Meanwhile, obtaining circularly polarized phosphorescence (CPP) with a large dissymmetry factor (g_lum) is highly significant but rather challenging. Herein, two chiral Au(I)-containing enantiomers, namely (S,S)-1 and (R,R)-1, are prepared. (S,S)-1 and (R,R)-1 show different self-assembly behaviors as the degree of aggregation in solution changes, leading to the formation of a variety of CPP signals. Notably, non-mirror-image CPP, CPP with the high g_lum values of +2.78 × 10⁻² and −1.54 × 10⁻², chirality amplification and inversion from the two chiral Au(I) luminogens are accompanied by the variation of their self-assembly morphologies. Impressively, (S,S)-1 and (R,R)-1 exhibit aggregation-induced CPP with the same chiral direction, and this is the first time that the unidirectional CPL from chiral enantiomers under the identical external environment is observed. Their respective three polymorphic crystals of (S,S)-1 and (R,R)-1, each with different packing arrangements, are fortunately obtained. The polymorphs derived from (S,S)-1 or (R,R)-1 demonstrate both M-helix and P-helix stacking arrangements. Through investigating their CPP properties, stacking modes, and intermolecular interactions of these six types of crystals cultivated by (S,S)-1 and (R,R)-1, the mechanism of their self-assembly morphologies-dependent multiple patterns CPP characteristics of (S,S)-1 and (R,R)-1 is further understood. Additionally, both (S,S)-1 and (R,R)-1 show a force-triggered CPP quenching feature, and the chiral co-assembly system with the |g_lum| value reaching 0.11 is gained by a combination of the synthesized enantiomers and commercial achiral liquid crystal.

Triterpenoids exhibit remarkable pharmacological characteristics and have garnered significant research attention, owing to their unique backbone structures and numerous modification sites. Recent advancements in supramolecular chemistry have highlighted the potential of triterpenoids to form organized assemblies through noncovalent interactions, affording versatile functional properties. By leveraging their unique structural characteristics and biological activities, innovative strategies can be developed to enhance the efficacy and safety of biomedical therapies. This review describes the recent advances in triterpenoids serving as (i) functional groups for aggregation-induced emission, (ii) building blocks for self-transportation and drug delivery, (iii) potential gelators for rational hydrogel design, and (iv) cholesterol alternatives for optimizing lipid-based nanoparticles. The biomedical perspectives of triterpenoid-based supramolecular assemblies and potential bottlenecks in clinical translation are also discussed, with the hope of offering insights into future research and biomedical applications.

Cationic compounds with quaternary ammonium structures are one of the most commonly utilized antibacterial materials, which can effectively overcome the emergence of bacterial drug resistance. Systematic investigation on the structure-activity relationship of such cationic compounds is essential for the development of efficient antimicrobials toward different bacterial strains with clear antimicrobial mechanisms. In this study, we rationally designed and synthesized two quaternary ammonium photosensitizers with aggregation-induced emission (AIE) properties. One possesses a unilaterally charged and Janus-type structure with two positively charged moieties at one tail and two hydrophobic alkyl chains on the other side. The other is a bilaterally symmetric molecule bearing quaternary ammonium structures at both ends. The fluorescence staining experiments, bactericidal assays, and bacterial morphology analyses reveal that the Janus-type AIE luminogen show superior photodynamic antimicrobial activities possibly due to its better disruption of the bacterial membranes. Further theoretical study on the molecule-membrane interaction and molecular dynamics gains deeper insights into the intrinsic relationships between molecular structures and antibacterial activities, which provides a feasible design strategy for high-performance antimicrobial agents.

In this study, we present a novel multicomponent self-assembly approach that offers good potential for crafting heterometallic complexes with exceptional constitutional control. This method generates metal ions from a sacrificial anode by using an electric field, which then coordinates with a metal complex precursor. As a proof-of-concept demonstration, we successfully synthesized single crystals of a heterometallic platinum(II)-copper(I) (Pt[II]-Cu[I]) complex at an exceptionally rapid rate within 30 s by applying a voltage to an acetonitrile solution of [Pt(ppy)(CN)₂]⁻Bu₄N⁺, using copper foil as the anode. Intriguingly, by finely adjusting the intensity and duration of the electric field, we achieved a variety of supramolecular structures, spanning from spherical to rod-like and even flower-like morphologies. Additionally, we found that the photoluminescence property of the resultant crystal can be reversibly shifted among green, orange, and cyan by merely altering the solvent environment. Finally, the crafted heterometallic Pt(II)-Cu(I) complex has shown great promise in advanced anti-counterfeiting applications.

The supramolecular polymerization of porphyrin dyad (PD) shows the pathway complexity leading to the formation of kinetically metastable nanoparticles (PD_Particle) through rapid cooling and thermodynamically stable fibrous supramolecular polymers (PD_Fiber) through slow cooling. The kinetically metastable PD_Particle is gradually transformed to the thermodynamically stable PD_Fiber. Due to the inherent achirality of PD, AFM images exhibited a random distribution of both M and P helices. Introducing chiral alkyl chains achieved a predominant helicity in PD_Fiber, with (S)-PD favoring M helices and (R)-PD favoring P helices. The addition of chiral 2-methyl pyrrolidine (MePy) further influences this transformation by retarding the transition from PD_Particle to PD_Fiber through axial coordination with the zinc porphyrin units, affecting the helicity of the resulting supramolecular polymer. By manipulating the cooling rates and environmental conditions, we demonstrate the reversible control over circular dichroism (CD) and circularly polarized luminescence (CPL), providing insight into the relationship between structural chirality and optical activity.

Two novel 18-crown-6-ether (18-C-6) directed one-dimensional silver(I) coordination polymers (1D Ag(I) CPs), formulated as {[(18-C-6)Ag(bpy)]·X}_∞ and {[(18-C-6)Ag(pyz)]·X}_∞ {bpy = 4,4′-bipyridine; pyz = pyrazine; X = BF₄⁻ (Ia, IIa), CF₃SO₃⁻ (Ib, IIb)}, are prepared and structurally determined. The protection of the 18-C-6 macrocycle not only efficiently prevents intermolecular interactions within each 1D Ag(I) CP but also significantly enhances the rigidity of the chain structures, allowing these polymers to exhibit remarkable phosphorescence with intense green-light emission at room temperature. Moreover, IIa and IIb show enhanced photoluminescence quantum yields and aggregation-induced emission properties, which can be attributed to their close-packed structure modes in the crystalline states. Interestingly, upon mixing with commercial resin, IIa can serve as an efficient and stable luminescent ink for 3D printing. The resulting printed structures demonstrate exceptional irradiation stability, retaining their luminescence properties without any quenching over a three-month period. This work not only provides a facile strategy to prepare luminescent 1D Ag(I) CPs but also shows the promise of their utilization in optical devices.

Benzo[d]thiazol-2-ylmethanol undergoes progressive oligomerization under solvothermal conditions in the presence of FeCl₃·6H₂O, yielding a heterocyclic aggregate, namely 1,2,3-tris(benzo[d]thiazol-2-yl)-2,9-dihydrobenzo[b]cyclopenta[e][1,4]thiazine. Single-crystal X-ray diffraction analysis was conducted on four distinct compounds isolated during the reaction, and electrospray ionization mass spectrometry (ESI-MS) of both solid products and intermediate reaction solutions enabled the identification of 15 consecutive reaction steps, where Fe(III) was directly involved in eight steps. These transformations comprise nine intermolecular C─C coupling events and six intramolecular ring expansion processes. The heteroatoms (N, O, and S) play distinct mechanistic roles according to their positions within the heterocyclic framework: (1) nitrogen and oxygen coordinate with Fe(III), facilitating activation of the reaction site; (2) homolytic cleavage of the C─O bond promotes C─C coupling reactions; and (3) C─S migration induces intramolecular ring expansion. Notably, theoretical calculations indicate a decrease in Gibbs free energy along the intramolecular reaction pathways, substantiating the proposed mechanism and activation mode, which underscores the essential role of Fe(III) in enabling the reaction progression. Furthermore, an investigation of the photophysical properties revealed that the resulting heterocyclic aggregates exhibit strong luminescence within the 535–610 nm wavelength range, approaching the near-infrared region. These findings highlight the significance of this reaction pathway in the controlled synthesis of functional oligomers and polymers from monomeric precursors, particularly through catalysis by cost-effective metal ions.

Membranes offer an attractive route to efficient enantioseparation, especially compared with energy-intensive techniques like chromatography. However, tuning membrane structure and porosity to separate chiral molecules remains challenging. Here, we present a process for producing intrinsically chiral, ordered discrete metallacycycle 1 membranes on polyacrylonitrile supports through interfacial coordination-driven self-assembly using organic precursor 2 and metallic precursor 3. These chiral membranes, with their orientated architecture, exhibit ultra-high enantioselectivity (up to 100%) and permeation efficiency for racemic 1-phenylethanol, 1-phenylethylamine, and 2-phenylglycinol. Thermodynamic data and molecular simulations revealed the retarded transport mechanism of the membrane, resulting in highly efficient enantioseparation. Notably, when integrated into a circuit-controlled 3D-printed module, the aligned metallacyclic membrane retained its enantioselectivity for high-value pharmaceutical racemic salbutamol. This approach provides a feasible strategy for creating supramolecular metallacyclic channels in chiral membranes, demonstrating the potential for accurate enantioseparations.

Ultra-small nanoparticles, nanowires, and two-dimensional nanosheets have attracted much attention in acute kidney injury (AKI) treatment. However, the influence of nanostructure geometry on AKI therapy remains unknown. It is important to investigate their biodistribution, clearance, and toxicology to identify the most potential geometry for further nanomedical applications. Herein, three types of oxygen-deficient tungsten oxide (WO_x) nanostructures, nanodots, nanowires, and nanosheets, with attractive reactive oxygen species (ROS) scavenging and computed tomography (CT) imaging properties are bottom-up synthesized, and their in vivo behaviors are systematically studied. The biodistribution results demonstrate that all three WO_x nanostructures can penetrate from the kidney and excrete to the bladder. Interestingly, nanodots can accumulate and be cleared quickly from the kidney, while nanosheets have long retention in vivo. In marked contrast to nanodots and nanosheets, nanowires show high levels in the lung organs with significant cytotoxicity. Therapeutic experiments suggest that nanodots and nanosheets have better therapeutic effects on AKI, but the therapeutic effect of nanowires is not obvious. Furthermore, the nanosheets perform better in alleviating AKI at a lower injection dose than nanodots. This work demonstrates that nanosheets, among various geometries, have particular potential for further AKI treatment because of outstanding performance in CT imaging, renal targeting, long-time retention, and low toxicity. The “structure-function” correlations enable the reasonable design of nanoprobes for AKI theragnostic.

The vasculature, as the essential biological network for oxygen and nutrients delivery and the dynamic regulatory center for physiological processes, is fundamentally important for maintaining human health and life quality. Accurate visualization of vascular structures, as well as real-time monitoring of hemodynamic parameters and molecular profiles associated with vascular function, are therefore crucial for early diagnosis and preventive interventions of vascular diseases. Fluorescence imaging technology, particularly in the second near-infrared window (NIR-II; 1000–1700 nm), offers distinct advantages for these demanding imaging requirements not only due to its high sensitivity, excellent spatial resolution, and real-time monitoring capability but also thanks to the superior signal-to-background ratio and large tissue penetration depth of NIR-II fluorescence. Among diverse NIR-II fluorescent probes, aggregation-induced emission luminogens (AIEgens) stand out for their intrinsic organic nature and, more importantly, for their unique aggregation-enhanced emission properties, which clearly differentiates them from traditional fluorophores and enable high-resolution imaging. Currently, a series of high-performance NIR-II AIEgens featuring relatively high fluorescence brightness and long emission wavelengths with emission tails even extending into the NIR-IIa (1300–1400 nm) and NIR-IIb (1500–1700 nm) subwindows have been reported and demonstrated encouraging results in intravital fluorescence angiography. This minireview summarizes recent advances in NIR-II AIEgens for various vascular imaging applications, categorized by anatomical locations, including cerebral, abdominal, hindlimb, ear, axillary, renal, and tumor angiography. The molecular design strategies and nanoengineering approaches to achieve longer emission wavelengths, higher fluorescence brightness, and improved bioavailability are highlighted. Finally, the remaining challenges and future directions are discussed from the aspects of materials engineering, application scenarios expansion, and clinical translation.

Unraveling the nanoscale distribution of small molecules in cells is of central importance for the understanding of cellular functions and the development of drugs. However, particularly the visualization of lipids such as cholesterol—a central compound of cell membranes—with high spatial resolution remains challenging because they cannot be efficiently immobilized for super-resolution microscopy investigations. Here we developed an azido- and amino-modified cholesterol probe that can be efficiently fixed and labeled with fluorophores by click chemistry. In combination with expansion microscopy, its cellular localization and interaction with other cellular proteins can be precisely determined in fixed cells at varying time points after addition. Our approach allows us to detect the endocytic pathway of cholesterol with unprecedented spatial resolution and shows that cholesterol is efficiently ingested in endocytic vesicles and accumulates as cholesterol aggregates with an average size of ∼37 nm in late endosomes and lysosomes, respectively.