2D materials are regarded as promising electrocatalysts for water splitting because of their advances in providing ample active sites and improving electrochemical reaction kinetics. 2D MoSe2 has a greater intrinsic electrical conductivity and lower Gibbs free energy for reactant adsorption. However, there is still room for improvement in the electrocatalytic performance of MoSe2 for high-performance electrochemical water splitting devices. Herein, the in situ preparation of heterostructure made of covalently bonded MoSe2 and rGO is reported. The obtained electrocatalyst contains the aggregated 3D structured MoSe2 over rGO, which is covalently bonded together with more edge sites. The active edge sites of MoSe2/rGO are dynamically involved in the electrocatalytic activity while facilitating electron transfer. Hence, the MoSe2/rGO heterostructure requires a low cell voltage of 1.64 V to reach 100 mA cm-2 in water splitting with high reaction kinetics. The aggregated MoSe2 over rGO with more edge sites exposed by the 3D structure of MoSe2 and the interfacial covalent bond in between them provides a favorable electronic structure for the HER and OER with low overpotentials and high current densities and enhances the stability of the electrocatalyst. This work presents an attractive and cost-effective electrocatalyst suitable for industrial-scale hydrogen fuel production.
The induction of tumor carbonyl stress is reported to efficiently revert immune suppression in the tumor microenvironment and enhance cancer immunotherapy. However, low oxygen concentration due to inherent tumor hypoxia limits its catalytic effect. Herein, an injectable thermosensitive hydrogel system (named APH) is developed for co-loading of near-infrared (NIR) aggregation-induced emission (AIE) nanoparticles and plasma amine oxidase (PAO) for boosting carbonyl stress and enhancing antitumor immunity. Upon 808 nm NIR laser irradiation, the AIE nanoparticles trigger a mild-temperature (around 45°C) photothermal effect in the tumor site, which significantly relieves tumor hypoxia and promotes the catalytic effect of released PAO to inhibit the growth of Myeloid-derived suppressor cells. Remarkably, the synergistic therapeutic effect of APH is verified through a significant inhibitory effect on the distant tumor, enhanced immune memory, and effective suppression of postoperative recurrence, rechallenge, and metastasis. Overall, the combined effect of AIE-mediated photothermal therapy and carbonyl stress by APH upon NIR irradiation therapy can significantly activate cancer immunotherapy, making it a promising treatment approach for cancer treatment.
Designing a theranostic probe for noninvasive bone imaging and bone disease therapy is both challenging and desirable. Herein, an ultrasmall Au nanocluster (NC, <2 nm)-based theranostic probe is developed to achieve highly temporospatial in vivo bone-targeted photoluminescence (PL) imaging in the second near-infrared window (NIR-II) and enhanced rheumatoid arthritis (RA) therapy. The key design of the probe involves the surface phosphorylation of atomically precise NIR-II emitting Au44 NCs. This phosphorylation enhances the bone-targeting ability of the probe due to the highly concentrated phosphate groups, allowing the probe to realize in vivo bone-targeted NIR-II PL imaging. Moreover, benefiting from the enhanced bone-targeting ability, ultrasmall hydrodynamic diameter, and excellent anti-inflammation and immunomodulatory effects, the probe not only demonstrates superior therapeutic efficacy for RA rats, effectively restoring the destructed cartilage to nearly normal but also exhibits good renal clearance and benign biocompatibility. These favorable attributes cannot be achieved by commercial methotrexate used for RA treatment. This study presents a new design paradigm for metal NC-based theranostic probes, offering the potential for high-resolution bone-targeted PL imaging and improved RA therapy.
Polymeric ultralong organic phosphorescence (UOP) with persistent emission is of great importance in practical applications. However, achieving good water-resistance for long-term environmental stability is a formidable challenge. In this contribution, through tailoring the alkyl-chain length of the hardeners and emitters, polymeric UOPs with varying crosslinking density and hydrophobic effect were obtained. Notably, all the polymers show no obvious decrease in UOP emission after high temperature-humidity test (85°C/85% relative humidity for 7 days). Detailed investigations demonstrate that the rigid covalent crosslinking networks suppress the quenching of triplet excitons while the hydrophobic microenvironment affords good water/moisture-resistance ability.Moreover, the polymers with superior processability are successfully applied as optical coatings, prepreg, and afterglow displays.With this work, we provide a new strategy to promote the long-term stability of polymeric UOP materials in high-temperature-humidity conditions.
The relaxation time under zero field reflects the memory retention capabilities of single-molecule magnets (SMMs) when used as storage devices. Intermolecular magnetic dipole interaction is ubiquitous in aggregates of magnetic molecules and can greatly influence relaxation times. However, such interaction is often considered harmful and challenging to manipulate in molecular solids, especially for high-performance lanthanide single-ion magnets (SIMs). By an elaborately designed combination of ion pairing and hydrogen bonding, we have synthesized two pseudo-D5h SIMs with supramolecular arrangements of magnetic dipoles in staggered and side-by-side patterns, the latter of which exhibits a 104-fold slower zero-field relaxation time at 2 K. Intriguingly, the side-by-side complex exhibits a significantly accelerated magnetic relaxation upon diamagnetic dilution, contrary to the general trend observed in the staggered complex. This strongly reveals the presence of aggregation-induced suppression of quantum tunneling in a side-by-side arrangement, which has not been observed in mononuclear SMMs. By leveraging ion-pairing aggregation and converting to a side-by-side pattern, this study successfully demonstrates an approach to transform a harmful intermolecular dipole interaction into a beneficial one, achieving a τQTM of 980 s ranking among the best-performance SMMs.
The rational design of Z-scheme heterojunction photosystems based on covalent organic frameworks (COFs) is a promising strategy for harnessing solar energy for hydrogen conversion. Herein, a direct Z-scheme single-atom photocatalyst based on COF and metal-organic ring has been constructed through the supramolecular interactions of coral-like COF (S-COF) and photosensitized Pd2L2 type metal-organic ring (MAC-FA1). The MAC-FA1/S-COF heterojunction exhibits good light absorption, efficient charge separation and transfer, slow electron-hole recombination, and highly dispersed Pd active sites, enabling an efficient and stable H2 evolution reaction. The optimized 4% MAC-FA1/S-COF achieves an H2 evolution rate of 100 mmol g-1 h-1 within 5 h and obtains a total accumulated turn-over number relative to Pd (TONPd) of 437,685 within 20 h, far superior to S-COF,MAC-FA1,M- 5/S-COF, Pd/S-COF, and M-5/Pd/S-COF, which is one of the highest records among COF-based photocatalysts for solar-driven H2 evolution. This is the first work to incorporate photosensitized metal-organic rings/cages into porous crystalline COFs to form a supramolecular Z-scheme heterojunction, which has significant potential as a high-performance photocatalyst for solar-driven H2 production.
The simultaneous achievement of chiral multiple-resonance thermally activated delayed fluorescence (MR-TADF) emitters with narrowband and circularly polarized electroluminescence (CPEL) poses a challenge. Herein, a MR-TADF emitter, Spiro-BNCz, embedding spirofluorene structure was developed and chiral separated, whose emission peaks at 528 nm in toluene with Commission Internationale de L’Eclairage coordinates of (0.26, 0.69). The conjugation extension caused by embedding sulfur substituted spirofluorene on B/N framework shortens the singlettriplet energy gap and increases spin-orbital coupling matrix element. Therefore, a fast reverse intersystem crossing rate constant of 2.8 × 106 s−1 and a high photoluminescence efficiency of 92% in film were achieved. The organic light-emitting diode (OLED) exhibits a maximum external quantum efficiency of 32.3%. Particularly, the circularly polarized OLEDs based on Spiro-BNCz enantiomers show symmetric CPEL with dissymmetry factors (|gEL|) ≈ 10−3.
Recombinant keratins possess strong hemostatic and wound healing properties but suffer from poor water solubility that restricts their bioactivities in biomedical applications. Herein, we report the rational design and synthesis of water-soluble keratins using a simple methodology named the QTY code. In vitro biophysical analyses and molecular dynamic simulation demonstrated a 200-fold increase in the water solubility of QTY variant keratins without apparent structural changes compared to native proteins. Homotypic self-assembly was observed for the first time in recombinant keratins in an aqueous environment, without urea and after QTY modification. Cell and animal experiments showed the in situ gel-forming capability of QTY variant keratins with superior hemostatic and wound healing activities at the wound sites compared to native recombinant keratins. Our work not only presented a simple and feasible pathway to produce large amounts of water-soluble keratins using QTY modification but also validated the enhanced self-assembly, hemostasis, and wound healing properties of these novel keratin species that may open up new venues for biomedical applications.
Outbreaks of infectious viruses offer a formidable challenge to public healthcare systems and early detection of viruses is essential for preventing virus propagation. In this work, an ultrasensitive plasmon-enhanced fluorescence resonance energy transfer (FRET) biosensor based on core-shell upconversion nanoparticle (csUCNP) and gold nanoparticle (AuNP) for accurate detection of SARS-CoV-2 viral RNA is presented. In this biodetection assay, the Tm3+/Er3+ co-doped csUCNP NaGdF4:Yb/Tm@NaYF4:Yb/Er acts as an energy donor and AuNP serves as an energy acceptor. The upconversion emission of Tm3+ and the design of the core-shell structure led to a simultaneous surface plasmon effect of AuNP. The localized surface plasmon resonance (LSPR) arising from collective oscillations of free electrons significantly enhanced FRET efficiency between Er3+ and AuNP. The as-prepared biosensor obtained a limit of detection (LOD) as low as 750 aM, indicating that the integration of FRET and surface plasmon into one biodetection assay significantly boosted the sensitivity of the biosensor. In addition, samples extracted from clinical samples are also utilized to validate the effectiveness of the biosensor. Therefore, this innovative plasmon-enhanced FRET biosensor based on Tm3+/Er3+ co-doped csUCNP may pave the way for rapid and accurate biodetection applications.
Controlled assembly of nanoparticles (NPs) has garnered much interest over the past two decades. Beyond established techniques, new methods utilizing local short-range or large-scale long-range interactions remain to be explored to achieve diverse micro- and nanoscale structures. Here, we report the controlled emergence of vortex-pair arrays within monodispersed gold nanorods by applying a direct current electric field across a pair of sawtooth electrodes. By employing in situ darkfield microscopy and particle collective analysis, we elucidate the mechanism behind the formation and stabilization of the NP vortices, attributing it to the combined effects of the electrode shape, high NP density, and high solution viscosity. We further explore the controllability of the vortex-pair arrays and obtain multiple complex vortice patterns. Our findings will facilitate the investigation of efficient and controlled dynamic assembly of NPs under external fields and help manufacture next-generation optoelectronic functional materials.
It is a matter of debate whether the discipline independence in discipline formation narrows its interdisciplinarity. It is also less well understood how disruptive works emerge in investigative practice rather than a theory-driven approach. Aggregationinduced emission (AIE) is an atypical photophysical phenomenon, in which the whole (aggregate) is brighter than the sum of its parts (single molecule). Through measuring and computing the cognitive extent and evolution of research on AIE, including topics, epistemic-social collaborative networks, interdisciplinarity, emergent concepts, core concept networks and knowledge flow, this study shows that a cross-research scales concept and its practice can establish new bridges in the sciences and promote disruptive work. Focusing on mesoscale entities, scientists from many different branches of science are involved in theoretical research on mechanisms, as well as developing different AIE systems for applications. The data analysis in this study provides details showing how non-reductionist concepts based on new scientific discoveries cross traditional disciplinary boundaries and aggregate interdisciplinary research. The emergence and evolution of the AIE field implies that scientists may be motivated to embrace nonreductionist ideas at different research scales, leading to a more permeable field boundary.
The development of high-performance organic blue light-emitting emitters is in urgent to act as an excitation source to contribute the white light generation. On the other hand, the investigation on optical waveguides have been received increasing attentions because they can manipulate the light propagation accurately in the microscale to boost the optoelectronic and energy conversion applications. In this work, we facilely prepared a deep-blue aggregation-induced emission (AIE) dye, namely TPP-4OMe, which shows high luminescent efficiency, narrow emission band and good stability in the aggregate state. TPP-4OMe can be fabricated as deep-blue AIE microfibers readily with definite morphology and composition. Based on the AIE microfibers, the active waveguide to transmit deep-blue emission signals can be achieved with a very low optical loss coefficient (α) of 6.7 × 10−3 dB µm−1. Meanwhile, the full-visible broadband low-loss passive waveguide can be well performed with these AIE microfibers, which has never been observed in the pure organic crystals. More interestingly, the excellent properties of AIE microfibers enable them to act as a wave-guiding excitation source, resulting in a distinct and pure white light emission. The present work not only provides excellent blue light-emitting materials but also bridges the waveguide to realize the efficient white light emission to accelerate the practical applications.
Scintillators, which can convert high-energy particles (X-rays) into detectable lowenergy ultraviolet-visible-near-infrared photons, are essential components of X-ray detectors and show extensive practical applications in nondestructive detection and medical imaging. Traditionally, inorganic scintillators represented by CsI:Tl have achieved definite progress. However, the harsh preparation conditions, high production cost, and poor mechanical properties impede their potential development in the high-end X-ray imaging field. Organic-inorganic hybrid metal complexes could be excellent alternatives, by virtue of their structural and spectral tunability, good solution processability, and excellent photophysical properties. This review mainly focuses on eco-friendly lead-free metal (Mn2+, Cu+, Sb3+, Sn2+, Ge2+, Ln3+, etc.) complex scintillators. The luminescence mechanisms are introduced and the scintillation performance, such as light yield, limit of detection, imaging resolution, etc., is highlighted. Moreover, the current challenges and perspectives in this emerging field are described. It is hoped to provide some theoretical guidance for the continuous development of the new scintillator systems.
Organic solar cells (OSCs) have demonstrated over 19% power conversion efficiency (PCE) with the help of material innovation and device optimization. Co-working with newly designed materials, traditional solvent additives, 1-chloronaphthalene (CN), and 1,8-diodooctane (DIO) are still powerful in morphology modulation towards satisfying efficiencies. Here, we chose recently reported high-performance polymer donors (PM6 & D18-Fu) and small molecular acceptors (Y6 & L8-BO) as active layer materials and processed them by different conditions (CN or DIO or none). Based on corresponding 12 groups of device results, and their film morphology characterizations (both ex-situ and in-situ ones), the property-performance relationships are revealed case by case. It is thereby supposed to be taken as a successful attempt to demonstrate the importance and complexity of donor-acceptoradditive interaction, since the device performance and physics analyses are also tightly combined with morphology variation. Furthermore, ternary blend construction for PCE improvement provides an approaching 19% level and showcases the potential of understanding-guided-optimization (UGO) in the future of OSCs.
As a unique type of supramolecular self-assemblies, crystalline host-guest aggregates have attracted extensive interests in multiple application fields. Herein, a crystalline host-guest aggregate LIFM-HG1 was obtained with curcubit[8]uril as the host and carboxypyridinium salt as the guest. Single-crystal structural analysis indicates that the presence of abundant weak interactions in LIFM-HG1 provides a rigid environment for the guest molecule and effectively blocks the external quenchers. Spectral analysis and theoretical calculations confirm the presence of robust triplet energy levels in LIFM-HG1. Even more impressively, the intersystem crossing channels of the guest molecules are greatly opened up after the formation of the crystalline host-guest aggregate, resulting in a large kisc of 6.70 × 107 s−1 at room temperature for LIFM-HG1 (which is ∼0 for pure guest), leading to fascinatingmultichannel (including one-photon, two-photon, and X-ray) excited LPL properties. In addition, the crystalline LIFM-HG1 has a much higher triplet state luminescence efficiency under X-ray and two-photon excitation than that under single-photon excitation (AP/AF = 86.8, 44.8, 10.7 under the three circumstances, respectively). And the phosphorescent emission intensity of LIFM-HG1 is 27.6 times higher than that of the crystalline guest under X-ray excitation. As a result, LIFM-HG1 shows a long afterglow retention time under both single- and two-photon excitation, and an impressive afterglow retention time of 1 s under X-ray excitation. Furthermore, the excellent lysosomal targeting and low cytotoxicity by the formation of host-guest aggregate makes LIFM-HG1 promising to be used as a novel lysosomal-targeted two-photon excited phosphorescent tracer.
Light-driven actuators are widely used for smart devices such as soft robots. One of the main challenges for actuators is achieving rapid responsiveness, in addition to ensuring favorable mechanical properties. Herein, we focused on photoresponsive polyurethane (CD-Azo-PU) based on controlling the crystallization of the hard segments in polyurethane (PU) by complexation between azobenzene (Azo) and cyclodextrins (CDs). CD-Azo-PU incorporated polyurethane as the main chain and a 1:2 inclusion complex between Azo and γCD as a movable crosslink point. Upon ultraviolet light (UV, λ = 365 nm) irradiation, the photoresponsiveness of CD-Azo- PU bent toward the light source (defined as positive), while that of the linear Azo polyurethane (Azo-LPU) without peracetylated γ-cyclodextrin diol (TAcγCD-diOH) as a movable crosslinker bent in the direction opposite the light source. The bending rates were determined to be 0.25°/s for CD-Azo-PU and 0.083°/s for Azo-LPU, indicating that the bending rate for CD-Azo-PU was faster than that for Azo-LPU. By incorporating movable crosslinks into CD-Azo-PU, we successfully achieved specific photoresponsive actuation with an enhanced rate.
Creation of new fluorophores is important for understanding the structure– property relationship, by which the required optical properties are likely to be attained. Herein, through theory calculation, it is found that furan-modified thiadiazolo quinoxaline acting as an electron acceptor can endow donor–acceptor– donor (D–A–D) type second near-infrared (NIR-II) fluorophores with longer emission wavelength than the other thiadiazolo quinoxaline-based acceptors containing pyridine, pyrrole, thiophene, and phenyl groups, respectively. On the basis of this theoretical prediction, a D–A–D type NIR-II fluorophore with 6,7-di(furan-2-yl)-[1,2,5]thiadiazolo[3,4-g] quinoxaline (DFTQ) as the acceptor and dithieno[3,2-b:2′,3′-d]pyrrole (DTP) as the donor is designed and synthesized, and the aggregation-induced emission (AIE) function is further achieved by introducing the AIE units of tetraphenylethylene (TPE) and triphenylamine (TPA), respectively, totally forming three NIR-II fluorophores DFTQ–DTP, DFTQ–DTPE, and DFTQ– DTPA. For biological applications, the fluorophores are encapsulated by amphiphilic DSPE–PEG2000 to generate water-dispersible nanoparticles (NPs). Almost the whole emission of each of the NPs falls into the NIR-II spectral range, with part emission beyond 1300 nm. By using DFTQ–DTPA NPs as the contrast and photothermal therapy (PTT) agent, high-resolution in vivo fluorescence imaging is achieved in the greater than 1300 nm window, and their good performance in photoacoustic imaging and high tumor PTT efficacy in tumor-bearing mice are also demonstrated. Taken together, this work mainly provides a strong electron acceptor for constructing longemitting fluorophores, and by using the electron acceptor, a AIE fluorophore with desirable quantum yield (QY) and photothermal conversion efficienciy (PCE) is synthesized and demonstrated to be promising in fluorescence/photoacoustic imaging and PTT.
Fluorescent-magneto nanoemitters have gained considerable attention for their applications in mechanical controlling-assisted optical signaling. However, the incompatibility between magnetic and fluorescent components often leads to functional limitations in traditional magneto@fluorescence nanostructure. Herein, we introduce a new compact-discrete spatial arrangement on a “fluorescence@magneto” core-shell nanostructure consisting of a close-packed aggregation-induced emission luminogen (AIEgen) core and a discrete magnetic shell. This structural design effectively eliminates the optical and magnetic interferences between the dual components by facilitating AIEgens loading in core region and reducing the magnetic feeding amount through effective exposure of the magnetic units. Thereby, the resulting magneto-AIEgen nanoparticle (MANP) demonstrates “win-win” performances: (i) high fluorescent intensity contributed by AIEgens stacking-enhanced photoluminescence and reduced photons loss from the meager magnetic shell; (ii) marked magnetic activity due to magneto extrapositionminimized magnetic shielding. Accordingly, the dual functions-retained MANP provides a proof of concept for construction of an immunochromatographic sensing platform, where it enables bright fluorescent labeling after magnetically enriching and separating procalcitonin and lipoarabinomannan in clinical human serum and urine, respectively, for the clinical diagnosis of bacterial infections-caused inflammation and tuberculosis. This study not only inspires the rational design of magnetic-fluorescent nanoemitter but also highlights promising potential in magneto-assisted point-of-care test and biomedicine applications.
Fluorogenic biosensors are essential tools widely used in biomedicine, chemical biology, environmental protection and food safety. Fluorescence resonance energy transfer (FRET) is a crucial technique for developing fluorogenic biosensors that provide mechanistic insight into bioprocesses through time-spatial bioimaging in living cells and organisms. Although extensive FRET-based sensors have been developed for detecting or imaging analytes of interest over the past decade, few comprehensive reviews have summarized the recent studies from the fundamental chemical angle about the design and application. In this work, the recent advance in the discovery of FRET biosensors using donor-acceptor dye combinations is described and they are classified based on different types of analytes, such as mall molecules, proteins, enzymes, nucleic acids and metal ions. This review provides molecular-level inspiration for the design of FRET-based biosensors, aiding in their application in biosensing and bioimaging.
In order to improve the performance of organic luminescent materials, lots of studies have been carried out at the molecular level. However, these materials are mostly applied as solids or aggregates in practical applications, in which the relationship between aggregation structure and luminescent property should be paid more attention. Here, we obtained five phenothiazine 5,5-dioxide (O-PTZ) derivatives with distinct molecular conformations by rational design of chemical structures, and systematically studied their room-temperature phosphorescence (RTP) effect in solid state. It was found that O-PTZ dimers with quasi-equatorial (eq) conformation tended to show stronger π-π interaction than quasi-axial (ax) conformers in crystal state, which was more conducive to the generation of RTP. Based on this result, a multi-level structural model of organic solids was proposed to draw the relationship between aggregation structure and RTP effect, just like the research for the structureproperty relationship of proteins. Using this structural model as the guide, boosted RTP efficiency from 1% to 20% was successfully achieved in the corresponding host-guest doping system, showing its wide applicability.
Amyloid-β peptide (Aβ) oligomers, characteristic symptom of Alzheimer’s disease (AD), have been identified as the most neurotoxic species and significant contributors to neurodegeneration in AD. However, due to their transient and heterogeneous nature, the high-resolution structures and exact pathogenic processes of Aβ oligomers are currently unknown. Using light-controlled molecular tweezers (LMTs), we describe a method for precisely capturing specific Aβ oligomers produced from synthetic Aβ and AD animal models. Light irradiation can activate LMTs, which are composed of two Aβ-targeting pentapeptides (KLVFF) motifs and a rigid azobenzene (azo) derivative, to form a tweezer-like cis configuration that preferentially binds to specific oligomers matching the space of the tweezers via multivalent interactions of KLVFF motifs with the oligomers. Surprisingly, cis-LMTs can immobilize the captured oligomers in transgenic Caenorhabditis elegans under light irradiation. The LMTs may serve as spatiotemporally controllable molecular tools to extract specific native oligomers for the structure and function studies via reversible photoisomerization, which would improve the understanding of the toxic mechanisms of Aβ oligomers and development of oligomer-targeted diagnosis and therapy.
Messenger RNA (mRNA) therapy is the intracellular delivery of mRNA to produce desired therapeutic proteins. Developing strategies for local mRNA delivery is still required where direct intra-articular injections are inappropriate for targeting a specific tissue. The mRNA delivery efficiency depends on protecting nucleic acids against nuclease-mediated degradation and safe site-specific intracellular delivery. Herein, novel mRNA-releasing matrices based on RGD-moiety-rich gelatin methacryloyl (GelMA) microporous annealed particle (MAP) scaffolds are reported. GelMA concentration in aerogel-based microgels (μgels) produced through a microfluidic process, MAP stiffnesses, and microporosity are crucial parameters for cell adhesion, spreading, and proliferation. After being loaded with mRNA complexes, MAP scaffolds composed of 10% GelMA μgels display excellent cell viability with increasing cell infiltration, adhesion, proliferation, and gene transfer. The intracellular delivery is achieved by the sustained release of mRNA complexes from MAP scaffolds and cell adhesion on mRNA-releasing scaffolds. These findings highlight that hybrid systems can achieve efficient protein expression by delivering mRNA complexes, making them promising mRNA-releasing biomaterials for tissue engineering.
Using household detergents to clean oil stains has always caused global concerns, as these detergents negatively impact the ecosystem and are toxic. Therefore, it is essential to effectively attenuate the adhesion force between oil stains and substrates to create an easy and detergent-saving cleaning pathway. To address this challenge, we herein develop a strategy to reduce the strength of oil adhesion on common substrates by ∼20 times through a lamination layer, which contains phase-transitioned lysozyme nanofilm (PTL) and cellulose nanocrystals (CNCs). The resultant CNC/PTL coating significantly enhances the capability of cleaning oil stains in an underwater detergent-free manner; this strategy is applicable to edible oil packaging material and tableware, without impairing the usability and aesthetics of these materials. This coating exhibits excellent mechanical stability and regeneration characteristics through simple soaking, ensuring its robustness in real applications in an infinite life cycle. By eliminating 100% detergent in routine cleaning, the CNC/PTL coating demonstrated remarkable cost-effectiveness, saving 57.7% of water and 83.3% of energy when washing tableware only with water. This work presents an ingenious design to create oil-repellent packaging materials and tableware toward detergent-free water-cleaning pathways, thereby greatly reducing the negative environmental impact of surfactant emissions.
The power conversion efficiency of organic photovoltaics (OPVs) has witnessed continuous breakthroughs in the past few years, mostly benefiting from the extensive use of a facile ternary blending strategy by blending the host polymer donor:small molecule acceptor mixture with a second small molecule acceptor. Nevertheless, this rather general strategy used in the well-known PM6 systems fails in constructing high-performance P3HT-based ternary OPVs. As a result, the efficiencies of all resulting ternary blends based on a benchmark host P3HT:ZY-4Cl and a second acceptor are no more than 8%. Employing the mutual miscibility of the binary blends as a guide to screen the second acceptor, here we were able to break the longstanding 10%-efficiency barrier of ternary OPVs based on P3HT and dual nonfullerene acceptors. With this rational approach, we identified a multifunctional small molecule acceptor BTP-2Br to simultaneously improve the photovoltaic performance in both P3HT and PM6-based ternary OPVs. Attractively, the P3HT:ZY-4Cl:BTP- 2Br ternary blend exhibited a record-breaking efficiency of 11.41% for P3HT-based OPVs. This is the first-ever report that over 11% efficiency is achieved for P3HTbased ternary OPVs. Importantly, the study helps the community to rely less on trial-and-error methods for constructing ternary solar cells.
Colloidal crystals are materials self-assembled from the colloidal nanoparticles. Due to the ordered microstructure, they exhibit significant optical properties and have shown huge potential in the field of biosensing. Besides, the unique macroscopic shapes can also play a critical role in the sensing process. Here, we present a comprehensive discussion on the colloidal crystal-based biosensors with different topological shapes, including the development strategies of currently reported colloidal crystal particles, films, and fibers, and their recent progress in biosensing. In addition, the faced challenges and the possible solutions are also concluded and discussed. We expect this review can enrich the knowledge and encourage the communication of interdisciplinary researchers, thus promoting the further development and practical applications of colloidal crystal-based biosensors.
The unusual room-temperature phosphorescence (RTP) from the n electron-rich systems (without regular conjugated structure) has aroused great attention for structural designing and application development of RTP materials. Such emission has been ascribed to clusterization-triggered emission (CTE) via weak through-space conjugation of n electrons in the heteroatoms. However, there was suspicion on such RTP as impurity-induced result. Therefore, in-depth photophysical investigation and effective proof methods are needed to trace the origin of such RTP. Here, using the recently reported CTE phosphor boric acid as the example, a Jablonski diagram-based verification protocol was proposed to confirm the intrinsic luminescence of the n electrons-rich systems. Meanwhile, some other types of luminophores, that is, traditional phosphors, already reported impurity-induced and host-guest doping luminophores, were included for comparison. Overall, this work provides a basic paradigm for differentiating between the impurity-involved and the n electron-rich phosphors and will further deepen the understanding of nonconventional luminescence.
The side-chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors, which becomes an important strategy to optimize the photovoltaic performance of organic solar cells. In this work, we designed and synthesized three brand-new nonfused ring electron acceptors (NFREAs) OC4-4Cl-Ph, OC4-4Cl-Th, and OC4-4Cl-C8 with hexylbenzene, hexylthiophene, and octyl side chains on the π-bridge units. Compared with OC4-4Cl-Ph and OC4-4Cl-Th, OC4-4Cl-C8 with linear alkyl side chain has more red-shift absorption, which is conducive to obtaining higher short-circuit current density. Additionally, the OC4-4Cl-C8 film exhibits a longer exciton diffusion distance, and the D18:OC4-4Cl-C8 blend film displays faster hole transfer, weaker bimolecular recombination, and more efficient exciton transport. Furthermore, The D18:OC4-4Cl-C8 blend films may effectively form interpenetrating networks that resemble nanofibrils, which can facilitate exciton dissociation and charge transport. Finally, OC4-4Cl-C8-based devices can be created a marvellously power conversion efficiency (PCE) of 16.56%, which is much higher than OC4-4Cl-Ph (12.29%)- and OC4-4Cl-Th-based (11.00%) ones, being the highest PCE among the NFREA based binary devices. All in all, we have validated that side-chain engineering is an efficient way to achieve high-performance NFREAs.
The surface organs mainly comprise the superficial layers of various parts of the mammalian body, including the skin, eyes, and ears, which provide solid protection against various threats to the entire body. Damage to surface organs could lead to many serious diseases or even death. Currently, despite significant advancements in this field, there remain numerous enigmas that necessitate expeditious resolution, particularly pertaining to diagnostic and therapeutic objectives. The advancements in nanomedicine have provided a significant impetus for the development of novel approaches in the diagnosis, bioimaging, and therapy of superficial organs. The aggregation-induced emission (AIE) phenomenon, initially observed by Prof. Ben Zhong Tang, stands out due to its contrasting behavior to the aggregationcaused quenching effect. This discovery has significantly revolutionized the field of nanomedicine for surface organs owing to its remarkable advantages. In this review of literature, we aim to provide a comprehensive summary of recent advances of AIE lumenogen (AIEgen)-based nanoplatforms in the fields of detection, diagnosis, imaging, and therapeutics of surface organ-related diseases and discuss their prospects in the domain. It is hoped that this review will help attract researchers’ attention toward the utilization of this field for the exploration of a wider range of biomedical and clinical applications.
Nonconventional luminescent materials have been rising stars in organic luminophores due to their intrinsic characteristics, including water-solubility, biocompatibility, and environmental friendliness and have shown potential applications in diverse fields. As an indispensable branch of nonconventional luminescent materials, polysiloxanes, which consist of electron-rich auxochromic groups, have exhibited outstanding photophysical properties due to the unique silicon atoms. The flexible Si-O bonds benefit the aggregation, and the empty 3d orbitals of Si atoms can generate coordination bonds including N → Si and O → Si, altering the electron delocalization of the material and improving the luminescent purity. Herein, we review the recent progress in luminescent polysiloxanes with different topologies and discuss the challenges and perspectives. With an emphasis on the driving force for the aggregation and the mechanism of tuned emissions, the role of Si atoms played in the nonconventional luminophores is highlighted. This review may provide new insights into the design of nonconventional luminescent materials and expand their further applications in sensing, biomedicine, lighting devices, etc.
Diabetic foot ulcers (DFUs) are a serious and prevalent complication of diabetes. Current diagnostic options are limited to macroscopic wound analysis such as wound size, depth, and infection. Molecular diagnostics promise to improve DFU diagnosis, staging, and assessment of treatment response. Here, we developed a rapid and easy-to-use fluorescent pH-sensing bandage for wound diagnostics. In a fluorescent dye screen, we identified pyranine as the lead compound due to its suitable pH-sensing properties in the clinically relevant pH range of 6–9. To minimize the release of this dye into the wound bed, we screened a library of ionic microparticles and found a strong adhesion of the anionic dye to a cationic polymeric microparticle. These dye-loaded microparticles showed a strong fluorescence response in the clinically relevant pH range of 6–9 and a dye release below 1% after 1 day in biological media. The dye-loaded microparticles were subsequently encapsulated in a calcium alginate hydrogel to minimize the interaction of the microparticles with the wound tissue. This pH-sensing diagnostic wound dressing was tested on full thickness dorsal wounds of mice, and a linear fluorescence response (R2 = 0.9909) to clinically relevant pH values was observed. These findings encourage further development of this pH-sensing system for molecular diagnostics in DFUs.
Thermally activated delayed fluorescence (TADF) materials have numerous applications in energy conversion and luminescent imaging. However, they are typically achieved as metal-organic complexes or pure organic molecules. Herein, we report the largest Au-Ag-oxo nanoclusters to date, Au18Ag26(R1COO)12(R2C≡C)24(µ4-O)2(µ3-O)2 (Au18Ag26, where R1 = CH3-, Ph-, CHOPh- or CF3Ph-; R2 = Ph- or FPh-). These nanoclusters exhibit exceptional TADF properties, including a small S1-T1 energy gap of 55.5 meV, a high absolute photoluminescence quantum yield of 86.7%, and a microseconds TADF decay time of 1.6 µs at ambient temperature. Meanwhile, Au18Ag26 shows outstanding stability against oxygen quenching and ambient conditions. Atomic level analysis reveals the strong π...π and C-H...π interactions from the aromatic alkynyl ligands and the enhancement of metal-oxygen-metal interactions by centrally coordinated O2−. Modeling of the electronic structure shows spatially separated highest occupied molecular orbital and lowest unoccupied molecular orbital, which promote charge transfer from the ligand shell, predominantly carboxylate ligands, to O2--embedded metal core. Furthermore, TADF Au-Ag-oxo nanoclusters exhibit promising radioluminescence properties, which we demonstrate for X-ray imaging. Our work paves the way for the design of TADF materials based on large metal nanoclusters for light-emission and radioluminescence applications.
Organoids have emerged as a powerful platform for studying complex biological processes and diseases in vitro. However, most studies have focused on individual organoids, overlooking the inter-organ interactions in vivo and limiting the physiological relevance of the models. To address this limitation, the development of a multi-organoid system has gained considerable attention. This system aims to recapitulate inter-organ communication and enable the study of complex physiological processes. This review provides a comprehensive overview of the recent advancements in organoid engineering and the emerging strategies for constructing a multi-organoid system. First, we highlight the critical mechanical, structural, and biochemical factors involved in designing suitable materials for the growth of different organoids. Additionally, we discuss the incorporation of dynamic culture environments to enhance organoid culture and enable inter-organoid communication. Furthermore, we explore techniques for manipulating organoid morphogenesis and spatial positioning of organoids to establish effective inter-organoid communication networks.We summarize the achievements in utilizing organoids to recapitulate inter-organ communication in vitro, including assembloids and microfluidic multiorganoid platforms. Lastly, we discuss the existing challenges and opportunities in developing a multi-organoid system from its technical bottlenecks in scalability to its applications toward complex human diseases.
The development of efficient drug delivery systems is essential for improving the efficacy and safety of cancer drugs, particularly for aggressive and difficult-totreat cancers. Covalent organic frameworks (COFs) are emerging as innovative porous nanomaterials in drug delivery systems (DDS), due to their unique properties, including the metal-free organic skeleton, predetermined structures and pore geometries, high porosity, large surface area, facile surface modification potential, and good biocompatibility. These characteristics make COFs excellent candidates for improving drug delivery by enhancing drug loading capacity and enabling precise encapsulation. This review emphasizes the importance of donor-acceptor-based COFs, which provide channels for charge transportation, and we also explore how the π-conjugated skeleton of COFs enhances its long-acting fluorescent properties and facilitates drug uptake via cell endocytosis. While this review primarily focuses on recent advancements in COF-based targeted DDS, it also acknowledges the challenges posed by the diverse pore geometries in porous materials and discusses potential solutions. Further, it underlines the potential of developing future drug carriers that can successfully and specifically target cancer cells, improving treatment efficiency while reducing adverse side effects.
Hydrogen-bonded organic frameworks (HOFs) are crystalline porous materials with permanent voids formed via self-assembly of organic molecules through hydrogen bonding and intermolecular forces. Further combination of HOFs with functional material would broaden their application horizon but were less explored in existing literature. Herein, a highly porous and photosensitive HOF was successfully coated onto upconversion nanoparticles (UCNPs) to construct a core-shell structure named UNCPs@PFC-73-Ni. To enhance spectral overlap and maximize energy conversion efficiency, this study utilized the Er and Tm co-doped UCNPs, which can effectively convert infrared light into visible light emission thereby exciting the porphyrin shell. Subsequent investigation reveals that the composite exhibits significant photodynamic and photothermal effects under infrared light. Encouraged by its noticeable photoactivity, UCNPs@PFC-73-Ni was evaluated as an antibacterial agent against Escherichia coli. Notably, significant antibacterial efficacy was observed, highlighting the potential of UCNPs@PFC-73-Ni as an effective antibacterial agent under infrared light irradiation.
Pickering multiphase systems stabilized by solid particles have recently attracted increasing attention due to their excellent stability. Among various solid stabilizers, natural and renewable cellulosic micro/nanoparticles that are derived from agricultural and forestry sources have become promising candidates for Pickering stabilization due to their unique morphological features and tunable surface properties. In this review, recent progress on forming and stabilizing Pickering multiphase systems using cellulosic colloidal particles is summarized, including the physicochemical factors affecting their assembly at the interfaces and the preparation methods suitable for producing Pickering emulsions. In addition, relevant application prospects of corresponding Pickering multiphase materials are outlined. Finally, current challenges and future perspectives of such renewable Pickering multiphase systems are presented. This review aims to encourage the utilization of cellulosic micro/nanoparticles as key components in the development of Pickering systems, leading to enhanced performance and unique functionalities.
Nonfused ring electron acceptors (NFREAs) are promising candidates for future commercialization of organic solar cells (OSCs) due to their simple synthesis. Still, the power conversion efficiencies (PCEs) of NFREA-based OSCs have large room for improvement. In this work, by merging end group halogenation and side chain engineering, we developed four A–D–A’–D–A type NFREAs, which we refer to as EH-4F, C4-4F, EH-4Cl, and C4-4Cl. Single crystal X-ray diffraction revealed that multiple intermolecular S...F interactions between cyclopentadithiophene and 5,6-difluoro-3-(dicyanomethylene)indanone could cause an unfavorable dimer formation, leading to ineffective π–π stackings in EH-4F and C4-4F, whereas no such dimer was found in EH-4Cl and C4-4Cl after replacing with 5,6-dichloro- 3-(dicyanomethylene)indanone. Moreover, although the shorter n-butyl side chain resulted in a closer molecular packing in C4-4Cl, EH-4Cl (2-ethylhexyl substitution) with proper crystallinity exhibited enhanced face-on orientation in thin film, which is favorable for vertical charge transport and further reducing charge recombination. As a result, a PCE of 13.0% is obtained for EH-4Cl-based OSC with a fill factor of 0.70. This work highlights the importance of molecular packing and orientation control toward future high-performance A–D–A’–D–A type NFREAs.
High-performance polymers have proliferated in modern society across a variety of industries because of their low density, good chemical stability, and superior mechanical properties. However, while polymers are widely applied, frequent fire disasters induced by their intrinsic flammability have caused massive impacts on human beings, the economy, and the environment. Supramolecular chemistry has recently been intensively researched to provide fire retardancy for polymers via the physical barrier and char-catalyzing effects of supramolecular aggregates. In parallel, the noncovalent interactions between supramolecular and polymer chains, such as hydrogen bonding, π-π interactions, metal-ligand coordination, and synergistic interactions, can endow the matrix with enhanced mechanical strength. This makes it possible to integrate physical-chemical properties and noncovalent interactions into one supramolecular aggregate-based high-performance polymeric system on demand. However, fulfilling these promises needs more research. Here, we provide an overview of the latest research advances of fire-retardant and high-strength polymer materials based on supramolecular structures and interactions of aggregates. This work reviews their conceptual design, characterization, modification principles, performances, applications, and mechanisms. Finally, development challenges and perspectives on future research are also discussed.
In biological systems, molecular assembly primarily relies on the assistance of molecular chaperones. Inspired by nature, strategies like ‘chaperone-assisted assembly’ and ‘catalyzed assembly’ have been proposed for the sophisticated control of molecular assembly. Nonetheless, significant challenges remain in the rational design of such systems, calling for a deep understanding of underlying principles. Herein, we demonstrate an artificial chaperone serves a dual role, that is catalyst in low dosages and inhibitor in high dosages, in regulating the supramolecular polymerization of peptides. Low dosages of carboxymethyl cellulose, as the chaperones, catalyze the assembly of Aβ16-22 peptides into fibrils through multi-step phase separation, while high dosages trap the peptides into coacervate intermediates and therefore inhibit the fibrillation. Consequently, the quantity of chaperones does not follow the intuition that ‘more is better’ for catalyzing assembly but instead has an optimal molar ratio. Investigation reveals that the interplay and evolution of electrostatic and hydrophobic interactions are the keys to achieving these processes. This study provides insights into the multifaceted roles artificial chaperones may play in a dosage-dependent manner and enriches the toolkit for efficient and controllable construction of complex assembly systems.
Stem cells, especially mesenchymal progenitors or mesenchymal stem cells (MSCs), possess an intrinsic property to form compact spheroid-like assemblies, a phenomenon known as cell aggregation. In recent years, a growing body of researches have uncovered that this is a cross-species conserved developmental event essential for initiating organogenesis in a variety of organs. Moreover, the self-assembly property also contributes to the regenerative capacities of MSC aggregates in vivo with broad range of applications in tissue engineering. In this review, the principles of self-assembled mesenchymal aggregation and its involvement in physiological organogenesis, as well as the construction approaches of engineering MSC aggregates and its application for organ regeneration are discussed. The authors aim to provide a speculative overview of the current understanding and the recent findings of cell aggregation, from both the developmental and the engineering perspectives, and thus offer insights into the understanding of stem cell biology and the establishment of novel organ regeneration strategies.