Synergistic changes between tumor-associated macrophages (TAMs) and tumor-associated fibroblasts (CAFs) aggravated immune evasion of hepatocellular carcinoma (HCC), however, the underlying molecular mechanisms remain elusive. Their continuous and dynamic interactions are subject to bioactive molecule changes. A real-time and in-situ monitoring method suitable for in vivo research of these processes would be indispensable but is scarce. In this study, a dual imaging strategy that tracing the TAMs and CAFs simultaneously was developed using a new arginase-specific probe and established CAFs-specific probe. The emerging roles of arginase in mediating CAFs activation in mice were explored. Results showed arginase up-regulation in TAMs, followed by proline increase. Subsequently, proline produced by TAMs initiated the activation of CAFs. Through the JAK-STAT signaling, CAFs up-regulated the PD-L1 and CTLA-4, ultimately promoting immune evasion of HCC. This study revealed a new mechanism by which TAMs and CAFs collaborate in immune evasion, providing new targets for HCC immunotherapy.

In this work, we demonstrate a chiral dual-core strategy for the design of high-performance organic circularly polarized aggregation-induced emission luminogens (AIEgens), which features of connecting two thermally activated delayed fluorescence (TADF) luminophore with chiral linkage that allows efficient through-space coupling (TSC) to occur. Using this strategy, a pair of dual-core enantiomers, R/S-DNKP, were designed and synthesized by linking two benzophenone derivatives with a 1,1’-bi-2-naphthol unit. Compared to the mono-core counterpart NKP, the dual-core emitters exhibited a much higher photoluminescence quantum yields of 94%. Moreover, benefited from their chiral helical folding configurations, the R/S-DNKP enantiomers exhibited a high luminescence dissymmetry factor (|glum|) value up to 1.3×10-3 in film states. Notably, the electroluminescence devices based on the R/S-DNKP enantiomers achieved external quantum efficiency values of 21.5% and 19.7% with little roll-off. It is believed that this molecular design strategy will pave new routes for the development of high-performance chiral emitters for future organic photonic devices.

Fluorescence imaging, a key technique in life science research, frequently utilizes fluorogenic probes for precise imaging in living systems. Tetrazine is an effective emission quencher in the design of fluorogenic probes, which can be selectively damaged upon bioorthogonal click reactions, leading to considerable emission enhancement. Despite significant efforts to increase the emission enhancement ratio upon click reaction (IAC/IBC) of tetrazine-functionalized fluorogenic probes, the influence of molecular aggregation on the emission properties has been largely overlooked in the design of these probes. In this study, we reveal that an ultrahigh IAC/IBC can be realized in the aggregate system when tetrazine is paired with aggregation-induced emission (AIE) luminogens. Tetrazine can increase its quenching efficiency upon aggregation and drastically reduce background emissions. Subsequent click reactions damage tetrazine and trigger significant AIE, leading to considerably enhanced IAC/IBC. We further showcase the capability of these ultra-fluorogenic systems in selective imaging of multiple organelles in living cells. We propose the term “Matthew Effect” in Aggregate Emission to describe the unique fluorogenicity of these probes, potentially providing a universal approach to attain ultrahigh emission enhancements in diverse fluorogenic aggregate systems.

The high curing temperatures required for traditional benzocyclobutene (BCB) materials have posed limitations on their applicability in high-temperature-sensitive fields. To address this challenge, our work focuses on the synthesis of a novel tetraphenylethylene (TPE)-functionalized BCB monomer, TPE-BCB, achieved through the introduction of an ether bond onto the BCB’s four-membered ring via Williamson reaction. TPE-BCB demonstrates remarkable low-temperature curing properties, characterized by a ring-opening peak temperature of 190 °C, representing a 25% reduction compared to conventional BCBs. Fully cured TPE-BCB resins exhibit exceptional dielectric and mechanical properties, coupled with minimal water absorption. Additionally, the incorporation of TPE with aggregation-induced emission (AIE) characteristics enhances the resins’ luminescence and photolithographic capabilities. Notably, our TPE-BCB resins achieve impressive photolithography performance with a resolution ratio of up to 10 µm. In contrast to conventional BCB-functionalized resins, TPE-BCB offers the dual advantage of low-temperature curing and luminescence. This development marks a significant step in the advancement of low-temperature curing BCB materials and serves as a pioneering example in the realm of multi-layer wafer bonding materials.

Melt electrowriting (MEW) is a solvent-free (i.e., no volatile chemicals), high-resolution 3D printing method that enables the fabrication of semi-flexible structures with rigid polymers. Despite its advantages, the MEW process is sensitive to changes in printing parameters (e.g., voltage, printing pressure, and temperature), which can cause fluid column breakage, jet lag, and/or fiber pulsing, ultimately deteriorating the resolution and printing quality. In spite of the commonly used error-and-trial method to determine the most suitable parameters, here, we present a machine learning (ML)-enabled image analysis-based method for determining the optimum MEW printing parameters through an easy-to-use graphical user interface (GUI). We trained 5 different ML algorithms using 168 MEW 3D print samples, among which the gaussian process regression ML model yielded 93% accuracy of the variability in the dependent variable, 0.12329 on root mean square error for the validation set and 0.015201 mean square error in predicting line thickness. Integration of ML with control feedback loop and MEW can reduce the error-and-trial steps prior to the 3D printing process, decreasing the printing time (i.e., increasing the overall throughput of MEW) and material waste (i.e., improving the cost-effectiveness of MEW). Moreover, embedding trained ML model with the feedback control system in a GUI facilitates a more straightforward use of ML-based optimization techniques in the industrial section (i.e., for users with no ML skills).

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 atom. The flexible Si-O bonds benefit the aggregation, and the empty 3d orbitals of Si atom can generate coordination bonds like 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.

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 towards 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, i.e. catalyst in low dosages and inhibitor in high dosages, in regulating the supramolecular polymerization of peptides. Low dosages of carboxymethyl cellulose, as the chaperones, catalyse 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 chaperone 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 between chaperones and peptides 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.

Topochemical reactions have been extensively studied in organic and polymer chemistry, and are conventionally triggered by heat and/or light. Pressure, as one of the fundamental thermodynamic parameters, has recently been applied to study phase transitions of inorganic and hybrid nanomaterials on both microscopic and macroscopic scales. Relatively fewer studies have been focused on high-pressure behaviors, especially pressure-induced reactions, on organic and polymer molecules and assemblies. Polytriacetylenes (PTAs) are unique conjugated polymers with all-carbon main-chains consisted of alternating double bonds and diacetylene units. Although diacetylene units are prime examples capable of light-induced topochemical polymerization into polydiacetylene, PTAs are found to be very stable under light irradiation. Here we report our observation that in a diamond anvil cell (DAC), applying low pressure leads to crystallization and ordering of PTAs bearing linear alkyl side-chains. Further increasing pressure leads to irreversible cross-linking reactions, resulting in materials of graphyne-like structures, appearances, optical properties, and solubilities. Findings in this paper thus reveal the potential of using pressure to guide conjugated polymer self-assembly and to induce chemical reactions toward new materials discoveries.