Aggregate (Hoboken, N.J.)最新文献

Multiresonant thermally activated delayed fluorescence (MR-TADF) emitters have been the focus of extensive design efforts as they are recognized to show bright, narrowband emission, which makes them very appealing for display applications. However, the planar geometry and relatively large singlet–triplet energy gap lead to, respectively, severe aggregation-caused quenching (ACQ) and slow reverse intersystem crossing (RISC). Here, a design strategy is proposed to address both issues. Two MR-TADF emitters triphenylphosphine oxide (TPPO)-tBu-DiKTa and triphenylamine (TPA)-tBu-DiKTa have been synthesized. Twisted ortho-substituted groups help increase the intermolecular distance and largely suppress the ACQ. In addition, the contributions from intermolecular charge transfer states in the case of TPA-tBu-DiKTa help to accelerate RISC. The organic light-emitting diodes (OLEDs) with TPPO-tBu-DiKTa and TPA-tBu-DiKTa exhibit high maximum external quantum efficiencies (EQE_max) of 24.4% and 31.0%, respectively. Notably, the device with 25 wt% TPA-tBu-DiKTa showed both high EQE_max of 28.0% and reduced efficiency roll-off (19.9% EQE at 1000 cd m⁻²) compared to the device with 5 wt% emitter (31.0% EQE_max and 11.0% EQE at 1000 cd m⁻²). The new emitters were also introduced into single-layer light-emitting electrochemical cells (LECs), equipped with air-stable electrodes. The LEC containing TPA-tBu-DiKTa dispersed at 0.5 wt% in a matrix comprising a mobility-balanced blend-host and an ionic liquid electrolyte delivered blue luminance with an EQE_max of 2.6% at 425 cd m⁻². The high efficiencies of the OLEDs and LECs with TPA-tBu-DiKTa illustrate the potential for improving device performance when the DiKTa core is decorated with twisted bulky donors.

Antimicrobial resistance (AMR) remains an urgent and formidable challenge to global public health. Developing new medicines or alternative therapies to address AMR is imperative. Herein, we rationally designed and synthesized a series of Au(I)-based aggregation-induced emission luminogens (AIEgens) to combat drug-resistant bacterial infections. Through systematic screening, we identified an optimal AIEgen, called complex 5, which can rapidly discriminate between gram-positive (G⁺) and gram-negative bacteria (G⁻) bacteria, and exert robust and broad-spectrum antimicrobial potency against diverse drug-resistant bacterial strains, including those intractable to treat in clinic. Furthermore, extensive testing against a variety of clinical drug-resistant isolates, coupled with the successful treatment of methicillin-resistant Staphylococcus aureus-infected skin wounds unequivocally validates the high efficiency and broad-spectrum activity of complex 5. Therefore, complex 5 emerges as a promising candidate for combating drug-resistant bacterial infections in clinic, and this work provides inspiration for developing new solutions to address the escalating global challenge of AMR.

To enhance the anesthetic efficacy and reduce toxic side effects, a strategy is proposed involving the utilization of general anesthetics of Propofol (Pro) and Etomidate (Eto) to synergistic inhibition GABA receptors simultaneously. Four-in-one molecular aggregates were prepared to implement this strategy, which comprised of Pro and Eto with the bridging molecule monoglyceride monooleate (GMO) and surfactant F127 through intermolecular forces. The blood-brain barrier (BBB) targeted lactoferrin (LF) is affixed to their surface, obtaining the final molecular aggregates. By employing lactoferrin enrich aggregates to the BBB, followed by ultrasound combine microbubbles to open the BBB, a remarkable 4.5-fold enhancement in brain drug delivery was achieved. The molecular aggregates group maintained stable parameters of heart rate, diastolic blood pressure, and systolic blood pressure. A notable increase of more than twice therapeutic index (TI) value was observed, implying their higher anesthesia efficiency and reduced toxicity. Electroencephalogram (EEG) experiments demonstrate a significant elevation in the proportion of δ waves from 28% to 80% for aggregates, accompanied by a nearly fivefold reduction in the proportion of θ waves, meaning a significant improvement in synergistic anesthesia effectiveness (interaction index 0.289) with lower drug dosage. Furthermore, mouse immunofluorescence brain slice experiments suggest Pro and Eto enter the GABA receptor simultaneously, resulting in synergistic inhibition of GABA receptors.

Dental caries is one of the most prevalent and costly biofilm-induced oral diseases that causes the deterioration of the mineralized tooth tissue. Traditional antimicrobial agents like antibiotics and antimicrobial peptides (AMPs) struggle to effectively eradicate bacteria in biofilms without eliciting resistance. Herein, we demonstrate the construction of FeOOH@Fe-Lysine@Au nanostructured AMPs (nAMPs) distinguished by their AMP-like antibacterial activity and self-producing reactive oxygen species (ROS) capacity for caries treatment. On the one hand, FeOOH@Fe-Lysine@Au nAMPs can catalyze glucose oxidation to generate ROS within the cariogenic biofilm microenvironment, resulting in the disintegration of the extracellular polymeric substance matrix and the exposure of bacteria. On the other hand, FeOOH@Fe-Lysine@Au nAMPs can attach to bacterial surfaces via electrostatic attractions, proceeding to damage membranes, disrupt metabolic pathways, and inhibit protein synthesis through the aggregated lysine and the generated ROS. Based on this antibacterial mechanism, FeOOH@Fe-Lysine@Au nAMPs can effectively eradicate Streptococcus mutans and its associated biofilm, significantly impeding the progression of dental caries. Given the straightforward and cost-efficient preparation of FeOOH@Fe-Lysine@Au nAMPs compared to AMPs that require specific sequences, and their minimal adverse impacts on gingival/palatal tissues, major organs, and oral/gut microbiomes, our research may promote the development of novel therapeutic agents in dental health maintenance.

The blockade of cytoprotective autophagy has been demonstrated to effectively enhance the efficacy of sonodynamic therapy (SDT). However, the limited recognition of antiautophagy agents for autophagosomes impedes the clinical application of autophagy inhibition. To efficiently deliver hydroxychloroquine (HCQ), an autophagy inhibitor, to autophagosomes, we utilized a strategy based on in situ click chemistry between sulfhydryl (-SH) and maleimide (Mal) groups to trigger autophagosomes tracking and suppress tumor growth synergistically. A cascade nanoreactor was synthesized by encapsulating Mal-modified HCQ (^MHCQ) into a manganese porphyrin-based metal-organic framework with sonosensitizer properties, followed by poly(ethylene glycol)ylated liposomal membrane coating. After ultrasound irradiation, SDT-induced apoptotic cells released damaged proteins with free -SH groups, which ^MHCQ rapidly captured in situ via a Mal-thiol click reaction. When autophagosomes actively wrapped damaged proteins for detoxification, they simultaneously internalized HCQ anchored on proteins. In this scenario, antiautophagy drugs could actively track intracellular autophagosomes instead of undergoing passive diffusion in the cytosol. The interaction between HCQ and autophagic vesicles was greatly enhanced, which strengthened the blocking efficiency of autophagy and resulted in complete cell death. Overall, this study with smart design provides a promising strategy for improving intracellular targeted delivery to autophagosomes, thereby enhancing antitumor therapy.

Integrated multimodal imaging in theranostics nanomaterials offers extensive prospects for precise and noninvasive cancer treatment. Precisely controlling the structural evolution of plasmonic nanoparticles is crucial in the development of photothermal agents. However, previous successes have been limited to static assemblies and single-component structures. Here, an activatable plasmonic theranostics system utilizing self-assembled 1D silver-coated gold nanochains (1D nanochains) is presented for precise tumor diagnosis and effective treatment. The absorbance of the adaptable core–shell chain structure can shift from visible to near-infrared (NIR) regions due to the fusion between nearby Au@Ag nanoparticles induced by elevated H₂O₂ levels in the tumor microenvironment (TME), resulting in the creation of a novel 3D aggregates with strong NIR absorption. With a high photothermal conversion efficiency of 60.2% at 808 nm, nanochains utilizing the TME-activated characteristics show remarkable qualities for photoacoustic imaging and significantly limit tumor growth in vivo. This study may pave the way for precise tumor diagnosis and treatment through customizable, optically tunable adaptive plasmonic nanostructures.

The hydrothermal/soft templating method is an effective way to synthesize ordered mesoporous carbon (OMC), yet the mechanism of this strategy is not well illustrated. Herein, a hydrothermal temperature-controlled approach is developed to precisely synthesize OMCs with well-defined morphologies from liquefied wood (LW). As the hydrothermal temperature increases from 130 to 210°C, the hydrophilicity of the hydrophilic blocks decreases accompanied by the increase of the relative volume of the hydrophobic block, resulting in the packing parameter p of micelles changing from p ≤ 1/3 to 1/3 < p < 1/2, which transforms the micelle's structure from spherical to cylindrical. Additionally, accelerated nucleation occurred with the increased hydrothermal temperature. When the rate of nucleation is matched to the self-assembly of the composite micelles, the composite micelles grow into worm-like morphology and an ordered p6m mesostructure. This hydrothermal temperature-controlled strategy provides a straightforward and effective approach for synthesizing OMCs with various morphologies from LW, addressing the previously insufficiently elucidated micelle formation mechanism in the hydrothermal/soft templating method.

It is crucial to realize the point-of-care (POC) testing of harmful analytes, capable of saving limited agricultural resources, assisting environmental remediation, ensuring food safety, and enabling early disease diagnosis. Compared with other conventional POC sensing strategies, aggregation-based analytical chemistry facilitates the practical-oriented development of POC nanosensors by altering the aggregation status of nanoprobes through the action of multiple aggregation-induced “forces” originating from the targets. Herein, we have proceeded with a comprehensive review focusing on the aggregation-based analytical chemistry in POC nanosensors, covering aggregation-induced “forces”, aggregation-induced signal transductions, aggregation-induced POC nanosensing strategies, and their applications in biomolecular monitoring, food safety analysis, and environmental monitoring. Finally, challenges existing in practical applications have been further proposed to improve their sensing applications, and we expect our review can speed up the development of cost-effective, readily deployable, and time-efficient nanosensors through aggregation-based analytical chemistry.

The waste of resources associated with fruit decay is rapidly spreading globally, threatening the interests of relevant practitioners and the health of consumer groups, and demanding precise solutions. Controlling fruit ripening through ethylene regulation is one of the most important strategies for providing high-quality fruits. However, current materials for ethylene regulation still have difficulty realizing their application potential due to high manufacturing costs and performance deficiencies. In this review, the ethylene-controlled release materials for ripening based on molecular encapsulation and the ethylene scavengers for preservation based on mechanisms such as oxidation, photodegradation, and adsorption are presented. We discuss and analyze a wide range of materials in terms of mechanism, performance, potential of applicability, and sustainability. The ethylene release behavior of encapsulating materials depends on the form in which the ethylene binds to the material as well as on environmental factors (humidity and temperature). For ethylene scavengers, there are a variety of scavenging mechanisms, but they generally require porous materials as adsorption carriers. We highlight the great opportunity of designing soft crystalline porous materials as efficient ethylene adsorbent due to their unique structural properties. We present this review, including a summary of practical characteristics and deficiencies of various materials, to establish a systematic understanding of fruit quality assurance materials applied to ethylene regulation, anticipating a promising prospect for these new materials.

The unfavorable photochemical processes at the molecular level have become a barrier limiting the use of aromatic amides as high-performance luminescent materials. Herein, we propose a reliable strategy for manipulating noncovalent conformational lock (NCL) via side-chain engineering to burst out eye-catching luminescence at the aggregate level. Contrary to the invisible emission in dilute solutions, dyad OO with a three-centered H-bond gave the wondrous crystallization-induced emission with a quantum yield of 66.8% and clusterization-triggered emission, which were much brighter than those of isomers. Theoretical calculations demonstrate that crystallization-induced planarized intramolecular charge transfer (PICT), conformation rigidification, and through-space conjugation (TSC) are responsible for aggregate-state luminescence. Robust NCL composed of intramolecular N-H···O interactions could boost molecular rigidity and planarity, thus greatly facilitating PICT and TSC. This study would inspire researchers to design efficient luminescent materials at the aggregate level via rational conformational control.