Aggregate (Hoboken, N.J.)最新文献

The hypoxic tumor microenvironment severely limits the effectiveness of photodynamic therapy (PDT) in hepatocellular carcinoma (HCC). To overcome this limitation, we designed and synthesized a dual-functional photosensitizer, PorRu, by conjugating a porphyrin unit with a ruthenium(II) polypyridyl complex through a flexible alkyl chain. PorRu is engineered to achieve specific accumulation in HCC cells and “dual-lock” binding with G-quadruplex DNA (G4 DNA). It demonstrated approximately 3–6 folds higher photocytotoxicity against HCC cells compared to its individual components, owing to enhanced tumor targeting and improved Type I photochemical reactivity. Unlike conventional oxygen-dependent PDT, PorRu efficiently generates reactive oxygen species (ROS) under near-infrared irradiation, directly oxidizing guanine bases in G4 DNA and causing extensive oxidative damage under both normoxic and hypoxic conditions. The ROS burst induces severe oxidative stress, mitochondrial dysfunction, and the release of mitochondrial DNA (mtDNA), ultimately activating the inflammasome and triggering pyroptosis. In vivo studies validated the potent tumor-suppressive capability of PorRu, highlighting its potential to circumvent hypoxia-induced therapy resistance. This work not only presents PorRu as a promising agent for precise HCC targeting but also offers a novel strategy to enhance PDT efficacy against hypoxic tumors.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world, exhibiting persistently high mortality rates due to delayed diagnosis and imprecise lesion localization. Leveraging the prevalent hypoxic microenvironment characteristic of CRC lesions, this study innovatively developed a PEGylated iridium-based near-infrared (NIR) hypoxia nanoprobe, Ir-PEG. This nanoprobe can be activated in situ under hypoxic conditions, providing high-contrast imaging of colonic lesions, even though the intestine is inherently a low oxygen environment. In vitro evaluation demonstrated that Ir-PEG had excellent oxygen sensitivity, water solubility, and deep tissue penetration capability. These properties enabled Ir-PEG to achieve precise imaging of CRC in the native colonic microenvironment. Remarkably, in both in vitro and in vivo models, Ir-PEG achieved highly sensitive detection of cancer cell populations, and could detect as few as 10⁴ CT26 cells in vivo. In addition, the nanoprobe could successfully identify different tumor types based on differential oxygen consumption rates across various cancer cells, suggesting its potential to identify intratumoral heterogeneity. As a molecular imaging tool, Ir-PEG enabled early non-invasive detection of CRC with high sensitivity and specificity, and holding significant promise for clinical translation.

Cooperative self-assembly based on multiple non-covalent interactions is ubiquitous in nature, yet the rational design of artificial cooperative systems remains challenging. Here we synthesize two carbazole derivatives, CbzE (with an ester group) and CbzA (with amide groups), to investigate how hydrogen bonding (HB) and halogen bonding (XB) jointly guide self-assembly into nanotubular supramolecular polymers. Using 1,4-diiodotetrafluorobenzene (DITFB) as XB donor or diplatinum(II) as linker, two types of [4 + 4] macrocycles are constructed and characterized by high-resolution mass spectrometry, ultraviolet-visible, infrared, and atomic force microscopy. CbzA, benefiting from strong HB, cooperatively assembles with DITFB into nanofibers and nanotubes, whereas CbzE, lacking amide groups, forms only disordered aggregates. Pt(II) coordination disrupts HB networks and redirects CbzA toward lateral aggregation, underscoring the sensitivity of assembly pathways to the balance of interactions. Remarkably, nanotubular CbzA + DITFB structures disassemble rapidly under trifluoroacetic acid vapor but are restored by triethylamine, demonstrating a reversible gel–sol–gel transition. This orthogonal acid/base responsiveness highlights the tunable and dynamic features of cooperative HB/XB systems. Overall, these results reveal the critical role of HB and XB cooperativity in directing ordered architectures and provide new design principles for intelligent supramolecular polymers with stimuli-responsive functions.

Cyanine dyes, despite their strong near-infrared (NIR) absorption, often undergo symmetry-breaking Peierls’ transitions in water known as the “cyanine limit,” resulting in suboptimal optical properties. In this work, we present a strategy to overcome this limitation by entrapping cyanine dye (Cy746) within the micellar nanoparticle (Np@M1-Cy746) of a bichromophoric [1+1] macrocycle M1 comprising of perylene diimide (PDI) and aza-BODIPY (Aza) that exhibits Förster resonance energy transfer (FRET), formed from an amphiphilic polymer 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)]. This approach not only stabilizes the cyanine dye but also enables two-step FRET from PDI to Aza of the macrocycle to Cy746, resulting in panchromatic absorption, enhanced NIR emission, and achieved near-white light emission. The micellar FRET assembly Np@M1-Cy746 also serves as a ratiometric temperature sensor with a sensitivity of 0.0379%°C⁻¹ and was utilized as a supramolecular photocatalyst in aqueous-phase photocatalytic Knoevenagel condensation of benzaldehyde and malononitrile. The two-step FRET process in Np@M1-Cy746 enabled its superior photocatalytic performance compared to the micelle of only M1 (Np@M1), which shows one-step FRET. This study offers a distinct approach for constructing multichromophoric macrocycle nanoparticles in aqueous media, leveraging upon its sequential energy transfer to achieve efficient and scalable photocatalytic transformation.

Aggregate celebrates its fifth anniversary this year. The journal has established itself as a leading platform for breakthroughs in aggregology—a field dedicated to the science of aggregate systems beyond isolated molecules. In this Editorial, we reflect on the journey so far and map out the exciting path forward.

Temperature-responsive luminescent materials hold great potential for applications in various advanced photoelectronic fields. However, realizing dual-mode, temperature-activated luminescence within a single molecular system remains a significant challenge. Here, two neutral Mn(II) complexes with dual-mode temperature-activated luminescent properties have been successfully synthesized by an alkoxy chain engineering strategy. At room temperature, these complexes are strongly emission-quenched. Reducing or increasing temperature triggers pronounced luminescence enhancement, due to the prohibition of thermal population to the upper lying quenching state or the removal of trace water molecules. Notably, this study provides the first definitive evidence of the dual-mode temperature-activated photoluminescent behavior in quartet excited states. Furthermore, simple digit-display patterns and anti-counterfeiting applications are demonstrated in this work.

Stereochemistry is a potent way to direct the molecular packing in condensed phases. Here, we synthesized the enantiopure, racemic, and achiral isomers of p-type small molecule, that is, indacenodithieno[3,2-b]thiophene, to understand the impact of stereochemistry on molecular packing and solid-state properties. In the solution state, the optical properties remain nearly identical among the isomers; however, a significant difference was observed in the condensed phase. X-ray diffraction pattern revealed enantiopure isomers were more tightly packed and exhibited strong π-stacking relative to their racemic and achiral counterparts. Two-dimensional arrangement of the stacked enantiopure isomers gives more dense-packed crystalline phases than an achiral analog, which is unusual anti-Wallach type condensed phases. The enantiopure one exhibited two times higher photoconductivity than its achiral or racemic analogues, as well as showing high electron spin polarizability (∼75%) with electrical current throughput (100 nA). The result highlights the role of stereochemistry as a key strategy to direct the condensed phase packing and properties in conjugated crystals.

With the rapid advancement of wearable electronics and bioelectronics, the construction of flexible energy-supplying systems that simultaneously integrate high-efficiency energy conversion, excellent body-conformability, and mechanical durability has emerged as a critical challenge urgently requiring breakthroughs in the thermoelectric field. Recently, Lei et al. have developed a robust thermoelectric elastomer that simultaneously exhibits a high thermoelectric figure of merit (ZT value), excellent tensile resilience, and low modulus. This innovation overcomes the long-standing challenge of balancing the “mechanical-electrical-thermal” performance of thermoelectric materials, thereby opening up new avenues for the continuous self-powering and solid-state cooling of wearable devices.

Zwitterionic hydrogels have attracted considerable attention as advanced biomaterials. However, the fabrication of traditional zwitterionic hydrogels typically relies on harsh polymerization conditions, and their backbone structures are non-biodegradable. In this study, we develop a self-aggregation-induced polymerization (SAIP) mechanism that enables the spontaneous formation of multifunctional zwitterionic hydrogels under mild aqueous conditions, utilizing a rationally designed lipoic acid-carboxybetaine monomer with lipoic acid-modified hyaluronic acid (LAHA) crosslinker. This SAIP mechanism is driven by the synergistic interaction between the strongly hydrophilic zwitterionic moieties and hydrophobic 1,2-dithiolanes, promoting monomer self-aggregation into high-concentration reactive microenvironments, thus facilitating efficient ring-opening polymerization without external catalysts or stimuli. The incorporation of LAHA as a crosslinker results in the formation of a stable zwitterionic hydrogel, distinguished by its mild preparation conditions, rapid spontaneous gelation (116 s), and controlled depolymerization through dynamic disulfide bonds. Furthermore, the resulting hydrogel demonstrates high water content (>76%), robust mechanical properties (compressive stress up to 3.86 MPa), exceptional antioxidant activity (>90% DPPH scavenging), high biocompatibility, and superior living cell encapsulation and protection. This study provides a fundamental understanding of hydrogel formation through the SAIP mechanism and advances the development of zwitterionic hydrogels, making the resulting hydrogel an attractive candidate for biomedical applications.