Aggregation-induced emission photosensitizer for antibacterial therapy of methicillin-resistant Staphylococcus aureus.

A cationic aggregation-induced emission photosensitizer (AIE-PS) MNNPyBB has been reported to have antibacterial effects against both Gram-positive and Gram-negative bacteria. The bacterial kill mechanism has been investigated and elucidated. In a methicillin-resistant Staphylococcus aureus subcutaneous infection model, wound closure has been achieved with normal re-epithelialization and preserved skin morphology.

Free Radical-Mediated Photocyclization of Triphenylphosphindole Oxides for Photoactivated and Self-Reported Lipid Peroxidation.

Photocyclization is demonstrated as a powerful tool for building complicated polycyclic molecules. And efficient photocyclization is competent as an artful strategy to develop photo-responsive smart materials. Herein, an efficient free radical-mediated photocyclization for triphenylphosphindole oxide (TPPIO) derivatives to generate tribenzophosphindole oxide (TBPIO) derivatives at ambient condition is reported. The reaction mechanism and substituent effect on photocyclization efficiency are thoroughly investigated. Additionally, photophysical and photochemical properties of TPPIO and TBPIO derivatives are measured for comparison and deeply deciphered by theoretical calculation. TPPIO derivatives own typical aggregation-induced emission feature but barely generate reactive oxygen species (ROS), while TBPIO derivatives experience aggregation-caused quenching but show efficient Type I ROS generation capacity. Further, in vitro experiments demonstrate that this photo-conversion can efficiently occur in situ in living cells to activate photodynamic therapy (PDT) effect to trigger lipid peroxidation with selective fluorescence "light up" in lipid droplet area under continuous irradiation. This work extends the optoelectronically and biologically interesting phosphindole oxide-containing π-conjugated systems through an efficient synthetic strategy, provides in-depth mechanistic descriptions in the aspects of reaction and property, and further presents their great potentials for photoactivated and self-reported PDT.

Structure and function of rice hybrid genomes reveal genetic basis and optimal performance of heterosis.

Exploitation of crop heterosis is crucial for increasing global agriculture production. However, the quantitative genomic analysis of heterosis was lacking, and there is currently no effective prediction tool to optimize cross-combinations. Here 2,839 rice hybrid cultivars and 9,839 segregation individuals were resequenced and phenotyped. Our findings demonstrated that indica-indica hybrid-improving breeding was a process that broadened genetic resources, pyramided breeding-favorable alleles through combinatorial selection and collaboratively improved both parents by eliminating the inferior alleles at negative dominant loci. Furthermore, we revealed that widespread genetic complementarity contributed to indica-japonica intersubspecific heterosis in yield traits, with dominance effect loci making a greater contribution to phenotypic variance than overdominance effect loci. On the basis of the comprehensive dataset, a genomic model applicable to diverse rice varieties was developed and optimized to predict the performance of hybrid combinations. Our data offer a valuable resource for advancing the understanding and facilitating the utilization of heterosis in rice.

Electrically driven organic laser using integrated OLED pumping.

Organic semiconductors are carbon-based materials that combine optoelectronic properties with simple fabrication and the scope for tuning by changing their chemical structure1-3. They have been successfully used to make organic light-emitting diodes2,4,5 (OLEDs, now widely found in mobile phone displays and televisions), solar cells1, transistors6 and sensors7. However, making electrically driven organic semiconductor lasers is very challenging8,9. It is difficult because organic semiconductors typically support only low current densities, suffer substantial absorption from injected charges and triplets, and have additional losses due to contacts10,11. In short, injecting charges into the gain medium leads to intolerable losses. Here we take an alternative approach in which charge injection and lasing are spatially separated, thereby greatly reducing losses. We achieve this by developing an integrated device structure that efficiently couples an OLED, with exceptionally high internal-light generation, with a polymer distributed feedback laser. Under the electrical driving of the integrated structure, we observe a threshold in light output versus drive current, with a narrow emission spectrum and the formation of a beam above the threshold. These observations confirm lasing. Our results provide an organic electronic device that has not been previously demonstrated, and show that indirect electrical pumping by an OLED is a very effective way of realizing an electrically driven organic semiconductor laser. This provides an approach to visible lasers that could see applications in spectroscopy, metrology and sensing.

Natural Coumarin Isomers with Dramatically Different AIE Properties: Mechanism and Application.

Aggregation-induced emission luminogens (AIEgens) are of great importance in optoelectronics and biomedical fields. However, the popular design philosophy by combining rotors with traditional fluorophores limits the imagination and structural diversity of AIEgens. Inspired by the fluorescent roots of the medicinal plant Toddalia asiatica, we discovered two unconventional rotor-free AIEgens, 5-methoxyseselin (5-MOS) and 6-methoxyseselin (6-MOS). Interestingly, a slight structural difference of the coumarin isomers leads to completely contrary fluorescent properties upon aggregation in aqueous media. Further mechanism investigation indicates that 5-MOS forms different extents of aggregates with the assistance of protonic solvents, leading to electron/energy transfer, which is responsible for its unique AIE feature, i.e., reduced emission in aqueous media but enhanced emission in crystal. Meanwhile, for 6-MOS, the conventional restriction of the intramolecular motion (RIM) mechanism is responsible for its AIE feature. More interestingly, the unique water-sensitive fluorescence property of 5-MOS enables its successful application for wash-free mitochondria imaging. This work not only demonstrates an ingenious tactic to seek new AIEgens from natural fluorescent species but also benefits the structure design and application exploration of next-generation AIEgens.

Molecular and Aggregate Synergistic Engineering of Aggregation-Induced Emission Luminogens to Manipulate Optical/Electronic Properties for Efficient and Diversified Functions.

The optical/electronic properties of organic luminescent materials can be regulated by molecular structure modification, which not only requires sophisticated and time-consuming synthesis but also is unable to accurately afford the optical properties of materials in the aggregate state. Herein, a facile strategy of molecular and aggregate synergistic engineering is proposed to manipulate the optical/electronic properties of a luminogen, ACIK, in the solid state for efficient and diversified functions. ACIK is facilely synthesized and exhibits three polymorphic states (ACIK-Y, ACIK-R, and ACIK-N) with a large emission difference of 102 nm from yellow to near-infrared (NIR). Their structure-property relationships were investigated by crystallographic analyses and computational studies. ACIK-Y, with the most twisted structure, exhibits an intriguing color-tuned fluorescence between yellow and NIR in the solid state in response to multiple stimuli. Shuttle-like ACIK-R microcrystals exhibit an optical waveguide property with a low optical loss coefficient of 19 dB mm-1. ACIK dots display bright NIR-I emission, large Stokes shift, and strong NIR-II two-photon absorption. ACIK dots show specific lipid droplets-targeting capability and can be successfully applied for two-photon fluorescence imaging of mouse brain vasculature with deep penetration and high spatial resolution. This study will inspire more insights in developing advanced optical/electronic materials based on a single chromophore for practical applications.

The Gain-of-Function Mutation, OsSpl26, Positively Regulates Plant Immunity in Rice.

Rice spotted-leaf mutants are ideal materials to study the molecular mechanism underlying programmed cell death and disease resistance in plants. LOC_Os07g04820 has previously been identified as the candidate gene responsible for the spotted-leaf phenotype in rice Spotted-leaf 26 (Spl26) mutant. Here, we cloned and validated that LOC_Os07g04820 is the locus controlling the spotted-leaf phenotype of Spl26 by reverse functional complementation and CRISPR/Cas9-mediated knockout of the mutant allele. The recessive wild-type spl26 allele (Oryza sativa spotted-leaf 26, Osspl26) is highly conservative in grass species and encodes a putative G-type lectin S-receptor-like serine/threonine protein kinase with 444 amino acid residuals. OsSPL26 localizes to the plasma membrane and can be detected constitutively in roots, stems, leaves, sheaths and panicles. The single base substitution from T to A at position 293 leads to phenylalanine/tyrosine replacement at position 98 in the encoded protein in the mutant and induces excessive accumulation of H2O2, leading to oxidative damage to cells, and finally, formation of the spotted-leaf phenotype in Spl26. The formation of lesions not only affects the growth and development of the plants but also activates the defense response and enhances the resistance to the bacterial blight pathogen, Xanthomonas oryzae pv. oryzae. Our results indicate that the gain-of-function by the mutant allele OsSpl26 positively regulates cell death and immunity in rice.

Highly Efficient Green and Red Narrowband Emissive Organic Light-Emitting Diodes Employing Multi-Resonant Thermally Activated Delayed Fluorescence Emitters.

Herein, we demonstrate how judicious selection of the donor decorating a central multi-resonant thermally activated delayed fluorescence (MR-TADF) core based on DiKTa can lead to very high-performance OLEDs. By decorating the DiKTa core with triphenylamine (TPA) and diphenylamine (DPA), 3TPA-DiKTa and 3DPA-DiKTa exhibit bright, narrowband green and red emission in doped films, respectively. The OLEDs based on these emitters showed record-high performance for this family of emitters with maximum external quantum efficiencies (EQEmax ) of 30.8 % for 3TPA-DiKTa at λEL of 551 nm and 16.7 % for 3DPA-DiKTa at λEL =613 nm. The efficiency roll-off in the OLEDs was improved significantly by using 4CzIPN as an assistant dopant in hyperfluorescence (HF) devices. The outstanding device performance has been attributed to preferential horizontal orientation of the transition dipole moments of 3TPA-DiKTa and 3DPA-DiKTa.

Information-Storage Expansion Enabled by a Resilient Aggregation-Induced-Emission-Active Nanocomposite Hydrogel.

Advanced materials with high performance and distinctive function are one of the main driving forces for the development of human society. The selection of appropriate materials and adequately utilizing their features to apply them in a specific area rationally are of great significance but remain challenging. Herein, an aggregation-induced emission (AIE)-active nanocomposite (NC) hydrogel is developed by introducing a pH-responsive AIE luminogen (AIEgen) into a Laponite XLS/polyacrylamide-based NC hydrogel (Laponite is a trademark of the company BYK Additives Ltd.). The AIEgen can protonate to interact with the negatively charged clay through the electrostatic interaction, which results in a drastic fluorescence enhancement due to the restriction of intramolecular motion by the rigid clay to the protonated AIEgen. This behavior facilitates the input of fluorescent information with a high contrast ratio in the hydrogel by acid stimulation. Moreover, by utilizing the excellent resilience of the hydrogel, hierarchically inputting and displaying the information in the original and stretched states of the hydrogel film is realized, which achieves information-storage expansion and dual-encryption via switching between stretching and restoring the film. This work showcases fully and synergistically utilizing the superiorities of various advanced materials to achieve superior applications and should guide the future development of advanced materials in emerging areas.

Excited-State Modulation in Donor-Substituted Multiresonant Thermally Activated Delayed Fluorescence Emitters.

Strategies to tune the emission of multiresonant thermally activated delayed fluorescence (MR-TADF) emitters remain rare. Here, we explore the effect of donor substitution about a MR-TADF core on the emission energy and the nature of the excited state. We decorate different numbers and types of electron-donors about a central MR-TADF core, DiKTa. Depending on the identity and number of donor groups, the excited state either remains short-range charge transfer (SRCT) and thus characteristic of an MR-TADF emitter or becomes a long-range charge transfer (LRCT) that is typically observed in donor-acceptor TADF emitters. The impact is that in three examples that emit from a SRCT state, Cz-DiKTa, Cz-Ph-DiKTa, and 3Cz-DiKTa, the emission remains narrow, while in four examples that emit via a LRCT state, TMCz-DiKTa, DMAC-DiKTa, 3TMCz-DiKTa, and 3DMAC-DiKTa, the emission broadens significantly. Through this strategy, the organic light-emitting diodes fabricated with the three MR-TADF emitters show maximum electroluminescence emission wavelengths, λEL, of 511, 492, and 547 nm with moderate full width at half-maxima (fwhm) of 62, 61, and 54 nm, respectively. Importantly, each of these devices show high maximum external quantum efficiencies (EQEmax) of 24.4, 23.0, and 24.4%, which are among the highest reported with ketone-based MR-TADF emitters. OLEDs with D-A type emitters, DMAC-DiKTa and TMCz-DiKTa, also show high efficiencies, with EQEmax of 23.8 and 20.2%, but accompanied by broad emission at λEL of 549 and 527 nm, respectively. Notably, the DMAC-DiKTa-based OLED shows very small efficiency roll-off, and its EQE remains 18.5% at 1000 cd m-2. Therefore, this work demonstrates that manipulating the nature and numbers of donor groups decorating a central MR-TADF core is a promising strategy for both red-shifting the emission and improving the performance of the OLEDs.

Intra- and Intermolecular Synergistic Engineering of Aggregation-Induced Emission Luminogens to Boost Three-Photon Absorption for Through-Skull Brain Imaging.

Three-photon fluorescence microscopic (3PFM) bioimaging is a promising imaging technique for visualizing the brain in its native environment thanks to its advantages of high spatial resolution and large imaging depth. However, developing fluorophores with strong three-photon absorption (3PA) and bright emission that meets the requirements for efficient three-photon fluorescence microscopic (3PFM) bioimaging is still challenging. Herein, four bright fluorophores with aggregation-induced emission features are facilely synthesized, and their powders exhibit high quantum yields of up to 56.4%. The intramolecular engineering of luminogens endows (E)-2-(benzo[d]thiazol-2-yl)-3-(7-(diphenylamino)-9-ethyl-9H-carbazol-2-yl)acrylonitrile (DCBT) molecules with bright near-infrared emission and large 3PA cross sections of up to 1.57 × 10-78 cm6 s2 photon-2 at 1550 nm, which is boosted by 3.6-fold to 5.61 × 10-78 cm6 s2 photon-2 in DCBT dots benefiting from the extensive intermolecular interactions in molecular stacking. DCBT dots are successfully applied for 3PFM imaging of brain vasculature on mice with a removed or intact skull, providing images with high spatial resolution, and even small capillaries can be recognized below the skull. This study will inspire more insights for developing advanced multiphoton absorbing materials for biomedical applications.

One-Pot Synthesis of Customized Metal-Phenolic-Network-Coated AIE Dots for In Vivo Bioimaging.

The integration of aggregation-induced emission luminogens (AIEgens) and inorganic constituents to generate multifunctional nanocomposites has attracted much attention because it couples the bright aggregate-state fluorescence of AIEgens with the diverse imaging modalities of inorganic constituents. Herein, a facile and universal strategy to prepare metal-phenolic-network (MPN)-coated AIE dots in a high encapsulation efficiency is reported. Through precise control on the nucleation of AIEgens and deposition of MPNs in tetrahydrofuran/water mixtures, termed as coacervation, core-shell MPN-coated AIE dots with bright emission are assembled in a one-pot fashion. The optical properties of MPN-coated AIE dots can be readily tuned by varying the incorporated AIEgens. Different metal ions, such as Fe3+ , Ti4+ , Cu2+ , Ni2+ , can be introduced to the nanoparticles. The MPN-coated AIE dots with a red-emissive AIEgen core are successfully used to perform magnetic resonance/fluorescence dual-modality imaging in a tumor-bearing mouse model and blood flow visualization in a zebrafish larva. It is believed that the present study provides a tailor-made nanoplatform to meet the individual needs of in vivo bioimaging.

Whole-Genome Sequencing of 117 Chromosome Segment Substitution Lines for Genetic Analyses of Complex Traits in Rice.

Rice is one of the most important food crops in Asia. Genetic analyses of complex traits and molecular breeding studies in rice greatly rely on the construction of various genetic populations. Chromosome segment substitution lines (CSSLs) serve as a powerful genetic population for quantitative trait locus (QTL) mapping in rice. Moreover, CSSLs containing target genomic regions can be used as improved varieties in rice breeding. In this study, we developed a set of CSSLs consisting of 117 lines derived from the recipient 'Huanghuazhan' (HHZ) and the donor 'Basmati Surkb 89-15' (BAS). The 117 lines were extensively genotyped by whole-genome resequencing, and a high-density genotype map was constructed for the CSSL population. The 117 CSSLs covered 99.78% of the BAS genome. Each line contained a single segment, and the average segment length was 6.02 Mb. Using the CSSL population, we investigated three agronomic traits in Shanghai and Hangzhou, China, and a total of 25 QTLs were detected in both environments. Among those QTLs, we found that RFT1 was the causal gene for heading date variance between HHZ and BAS. RFT1 from BAS was found to contain a loss-of-function allele based on yeast two-hybrid assay, and its causal variation was a P to S change in the 94th amino acid of the RFT1 protein. The combination of high-throughput genotyping and marker-assisted selection (MAS) is a highly efficient way to construct CSSLs in rice, and extensively genotyped CSSLs will be a powerful tool for the genetic mapping of agronomic traits and molecular breeding for target QTLs/genes.

Unveiling the crucial contributions of electrostatic and dispersion interactions to the ultralong room-temperature phosphorescence of H-bond crosslinked poly(vinyl alcohol) films.

Organic phosphors exhibiting room-temperature phosphorescence (RTP) in the amorphous phase are promising candidates for optoelectronic and biomedical applications. In particular, noncovalently embedding organic phosphors into a poly(vinyl alcohol) (PVA) matrix has emerged as the most commonly used yet effective approach to obtain amorphous organic RTP materials. While the role of intermolecular hydrogen-bonding interactions in determining the RTP properties of doping PVA systems has been well documented, we show that electrostatic and dispersion interactions contribute crucially to the ultralong RTP properties of doping PVA films. This impressive outcome reveals the nature of non-covalent interactions existing in doping PVA systems for the first time. We demonstrate this through detailed experimental and computational studies for a series of hydrogen-bond crosslinked PVA films where star-shaped organic phosphors containing active groups of carboxy, hydroxy, and amino act as multisite crosslinkers for the construction of extensive hydrogen-bonding networks. More importantly, we successfully obtain an ultralong RTP lifetime of up to 1.74 s by tuning the electrostatic and dispersion interactions between organic phosphors and the PVA matrix through simply modifying active groups of organic phosphors. This instructive work will provide new guiding principles for the exploration of amorphous organic RTP systems.

Precise Molecular Engineering of Type I Photosensitizers with Near-Infrared Aggregation-Induced Emission for Image-Guided Photodynamic Killing of Multidrug-Resistant Bacteria.

Multidrug resistance (MDR) bacteria pose a serious threat to human health. The development of alternative treatment modalities and therapeutic agents for treating MDR bacteria-caused infections remains a global challenge. Herein, a series of near-infrared (NIR) anion-π+ photosensitizers featuring aggregation-induced emission (AIE-PSs) are rationally designed and successfully developed for broad-spectrum MDR bacteria eradication. Due to the strong intramolecular charge transfer (ICT) and enhanced highly efficient intersystem crossing (ISC), these electron-rich anion-π+ AIE-PSs show boosted type I reactive oxygen species (ROS) generation capability involving hydroxyl radicals and superoxide anion radicals, and up to 99% photodynamic killing efficacy is achieved for both Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant Escherichia coli (MDR E. coli) under a low dose white light irradiation (16 mW cm-2 ). In vivo experiments confirm that one of these AIE-PSs exhibit excellent therapeutic performance in curing MRSA or MDR E. coli-infected wounds with negligible side-effects. The study would thus provide useful guidance for the rational design of high-performance type I AIE-PSs to overcome antibiotic resistance.

Phototriggered Aggregation-Induced Emission and Direct Generation of 4D Soft Patterns.

Microscopic control of macroscopic phenomena is one of the core subjects in materials science. Particularly, the spatio-temporal control of material behaviors through a non-contact way is of fundamental importance but is difficult to accomplish. Herein, a strategy to realize remote spatio-temporal control of luminescence behaviors is reported. A multi-arm salicylaldehyde benzoylhydrazone-based aggregation-induced emission luminogen (AIEgen)/metal-ion system, of which the fluorescence can be gated by the UV irradiation with time dependency, is developed. By changing the metal-ion species, the fluorescence emission and the intensity can also be tuned. The mechanism of the UV-mediated fluorescence change is investigated, and it is revealed that a phototriggered aggregation-induced emission (PTAIE) process contributes to the behaviors. The AIEgen is further covalently integrated into a polymeric network and the formed gel/metal-ion system can achieve laser-mediated mask-free writing enabled by the PTAIE process. Moreover, by further taking advantage of the time-dependent self-healing property of hydrazone-based dynamic covalent bond, transformable 4D soft patterns are generated. The findings and the strategy increase the ways to manipulate molecules on the supramolecule or aggregate level. They also show opportunities for the development of controllable smart materials and expand the scope of the materials in advanced optoelectronic applications.

Cytoplasmic and nuclear genome variations of rice hybrids and their parents inform the trajectory and strategy of hybrid rice breeding.

The male sterility (MS) line is a prerequisite for efficient production of hybrid seeds in rice, a self-pollinating species. MS line breeding is pivotal for hybrid rice improvement. Understanding the historical breeding trajectory will help to improve hybrid rice breeding strategies. Maternally inherited cytoplasm is an appropriate tool for phylogenetic reconstruction and pedigree tracing in rice hybrids. In this study, we analyzed the cytoplasmic genomes of 1495 elite hybrid rice varieties and identified five major types of cytoplasm, which correspond to different hybrid production systems. As the cytoplasm donors for hybrids, 461 MS lines were also divided into five major types based on cytoplasmic and nuclear genomic architecture. Specific core accessions cooperating with different fertility-associated genes drove the sequence divergence of MS lines. Dozens to hundreds of convergent and divergent selective sweeps spanning several agronomic trait-associated genes were identified among different types of MS lines. We further analyzed the cross patterns between different types of MS lines and their corresponding restorers. This study systematically analyzed the cytoplasmic genomes of rice hybrids revealed their relationships with nuclear genomes of MS lines, and illustrated the trajectory of hybrid rice breeding and the strategies for breeding different types of MS lines providing new insights for future improvement of hybrid rice.

Good Steel Used in the Blade: Well-Tailored Type-I Photosensitizers with Aggregation-Induced Emission Characteristics for Precise Nuclear Targeting Photodynamic Therapy.

Photodynamic therapy (PDT) has long been recognized to be a promising approach for cancer treatment. However, the high oxygen dependency of conventional PDT dramatically impairs its overall therapeutic efficacy, especially in hypoxic solid tumors. Exploration of distinctive PDT strategy involving both high-performance less-oxygen-dependent photosensitizers (PSs) and prominent drug delivery system is an appealing yet significantly challenging task. Herein, a precise nuclear targeting PDT protocol based on type-I PSs with aggregation-induced emission (AIE) characteristics is fabricated for the first time. Of the two synthesized AIE PSs, TTFMN is demonstrated to exhibit superior AIE property and stronger type-I reactive oxygen species (ROS) generation efficiency owing to the introduction of tetraphenylethylene and smaller singlet-triplet energy gap, respectively. With the aid of a lysosomal acid-activated TAT-peptide-modified amphiphilic polymer poly(lactic acid)12k-poly(ethylene glycol)5k-succinic anhydride-modified TAT, the corresponding TTFMN-loaded nanoparticles accompanied with acid-triggered nuclear targeting peculiarity can quickly accumulate in the tumor site, effectively generate type-I ROS in the nuclear region and significantly suppress the tumor growth under white light irradiation with minimized systematic toxicity. This delicate "Good Steel Used in the Blade" tactic significantly maximizes the PDT efficacy and offers a conceptual while practical paradigm for optimized cancer treatment in further translational medicine.

Biologically Excretable Aggregation-Induced Emission Dots for Visualizing Through the Marmosets Intravitally: Horizons in Future Clinical Nanomedicine.

Superb reliability and biocompatibility equip aggregation-induced emission (AIE) dots with tremendous potential for fluorescence bioimaging. However, there is still a chronic lack of design instructions of excretable and bright AIE emitters. Here, a kind of PEGylated AIE (OTPA-BBT) dots with strong absorption and extremely high second near-infrared region (NIR-II) PLQY of 13.6% is designed, and a long-aliphatic-chain design blueprint contributing to their excretion from an animal's body is proposed. Assisted by the OTPA-BBT dots with bright fluorescence beyond 1100 nm and even 1500 nm (NIR-IIb), large-depth cerebral vasculature (beyond 600 µm) as well as real-time blood flow are monitored through a thinned skull, and noninvasive NIR-IIb imaging with rich high-spatial-frequency information gives a precise presentation of gastrointestinal tract in marmosets. Importantly, after intravenous or oral administration, the definite excretion of OTPA-BBT dots from the body is demonstrated, which provides influential evidence of biosafety.

Robust Supramolecular Nano-Tunnels Built from Molecular Bricks*.

Herein we report a linear ionic molecule that assembles into a supramolecular nano-tunnel structure through synergy of trident-type ionic interactions and π-π stacking interactions. The nano-tunnel crystal exhibits anisotropic guest adsorption behavior. The material shows good thermal stability and undergoes multi-stage single-crystal-to-single-crystal phase transformations to a nonporous structure on heating. The material exhibits a remarkable chemical stability under both acidic and basic conditions, which is rarely observed in supramolecular organic frameworks and is often related to structures with designed hydrogen-bonding interactions. Because of the high polarity of the tunnels, this molecular crystal also shows a large CO2 -adsorption capacity while excluding other gases at ambient temperature, leading to high CO2 /CH4 selectivity. Aggregation-induced emission of the molecules gives the bulk crystals vapochromic properties.