Aggregate (Hoboken, N.J.)最新文献

Coulomb's law predicts that like-charge ions repel and avoid dimerization. However, a class of dimers between like-charge ions is characterized. The [3,3’-Fe(1,2-C₂B₉H₁₁)₂]⁻ (abbreviated as [o-FESAN]⁻) represents an innovative non-classical inorganic anion apart from hydroxyanions that exhibits anion-anion stabilization via dihydrogen bonding. Experimental methods (nuclear magnetic resonance [NMR], dynamic light scattering [DLS], and X-ray diffraction) and theoretical approaches (density functional theory) reveal that [o-FESAN]⁻ clusters aggregate by overcoming long-range electrostatic repulsion. The synthesis of [H₃O][o-FESAN]•3H₂O and its crystal structure confirm the formation of stabilized anion-anion aggregates, with [H₃O]⁺ counterions residing freely in the channels rather than between the anionic clusters. The structure exhibits the cisoid rotamer, which facilitates the ability of the anionic [o-FESAN]⁻ cluster to form interactions stabilized by dihydrogen bonds (head-to-middle cluster) shorter than the sum of the Van der Waals radii. These shorter bonds are crucial for the formation of anion-anion interactions mediated by dihydrogen bonds. X-ray structures show that anions aggregate in the solid state, overcoming long-range electrostatic repulsion through dihydrogen bonds, which are distinct from the hydrogen bonds commonly observed in anion systems involving highly electronegative elements. Consistent with crystal structure evidence, ¹H NMR, transmission electron microscopy, and DLS confirm [o-FESAN]⁻ anion-anion aggregates in solution. Theoretical calculations support the formation of these anion-anion aggregates, primarily via C_cluster-H···H-B bonds. While individual B-H···H-B interactions are weakly attractive, their cumulative effect significantly enhances aggregate stability. Additionally, the crystal structure of Na(H₂O)₃[o-FESAN] is reported and analyzed, providing further evidence of unconventional interactions stabilized by dihydrogen bonds.

Protein aggregation is an important pathological feature of cardiovascular disease. Therein, thrombin-mediated fibrin aggregation is one of the mechanisms of thrombosis, accurate monitoring of which is significant for the research of thrombosis. In this study, the optical properties and theoretical calculations confirmed that the AIE probe could specifically illuminate fibrin aggregates without interference, and its signal response was positively correlated with thrombin activity. Therefore, the biosensing technique can realize in situ monitoring of the coagulation process and rapid identification of active substances in complex systems. Furthermore, to detect anticoagulant active monomers, a biosensing targeted affinity screening (BioSTAS) technology was established by combining the above biosensing technique with the affinity chromatography technique. The rapid identification of active substances was achieved through biosensing, and then active monomers were captured by affinity chromatography. As a result, two agents with anticoagulant activity, rhein and oleanolic acid, were discovered via the screening of more than 30 kinds of natural products and commercial preparations. This study not only provides a new idea for the application of AIE probes in the dynamic monitoring of protein aggregation but also establishes an innovative strategy for screening active agents from a complex system through the integration of biosensing and affinity chromatography technologies.

Lignin, as one of the most abundant natural aromatic polymers, holds significant promise for high-value applications; however, its inherent dark coloration poses a major constraint for such uses. In this review, we systematically examine the key factors contributing to lignin's color, with a focus on structural alterations during extraction, the formation of chromophores, and the influence of molecular weight and morphology. We then provide a comprehensive overview of current decolorization strategies, including oxidative bleaching, hydroxyl shielding modification, physical methods, and biomass fractionation techniques. This review offers a detailed summary of both the mechanisms underlying lignin coloration and recent advances in decolorization, thereby providing valuable guidance for the optimization of whitening processes and facilitating the advanced utilization of lignin.

The electronic spectra and luminescence decay measurements at room temperature (RT) and 77 K have been recorded for pristine hexagonal and cubic CsCdCl₃ and for this material doped with Mn²⁺ or Fe³⁺. First-principles calculations have been performed in order to rationalize the results. The RT visible emission broad band of hexagonal CsCdCl₃ is due to [MnCl₆]⁴⁻ emission at two different Cd²⁺ sites. On cooling below RT, the Mn²⁺ emission weakens in intensity, and variable intensity near-ultraviolet emission bands are assigned to spin-orbit coupling mixed singlet and triplet ¹D₂, ³D_3,2,1 (4d⁹5s¹) → ¹A_1g (4d¹⁰) (O_h) transitions at C_3v and D_3d sites of Cd²⁺. Pristine cubic CsCdCl₃ exhibits two weak RT emission bands associated with tetrahedral and octahedral Mn²⁺ impurity. Doping hexagonal CsCdCl₃ with Fe³⁺ does not produce additional visible emissions and leads to quenching of Cd²⁺ emissions below RT. Very weak infrared emission from Fe³⁺ is observed. The thermoluminescence of cubic and hexagonal CsCdCl₃ is weak, but long-lasting persistent luminescence is obtained upon Mn²⁺ doping at a several percent level. Optical applications for anti-counterfeiting and information encryption are suggested.

This work presents a facile strategy to synthesize high-performance trichromatic carbon dots by precisely modulating the o-phenylenediamine/phytic acid molar ratio. Comprehensive experiments and theoretical calculations reveal three distinct emission origins: molecule states, carbon core states, and clusteroluminescence. Their excellent optical properties enable applications in tunable phosphor-converted LEDs, luminescent solar concentrators, and a self-powered integrated photovoltaic system (e70167).

This study presents a new class of amphiphilic porous frameworks constructed through ion-dipole interactions between anionic silicate cages and K⁺ ions. These materials uniquely integrate solid-state porosity, demonstrated by selective gas adsorption, with molecular-scale solution processability. Remarkably, the materials preserve the discrete integrity of their cages in solution, enabling host–guest recognition. They can also be reversibly regenerated, offering a versatile strategy for designing multifunctional, amphibious porous materials (e70157).

Since Aggregate's inaugural issue in December 2020, we have embarked on the wonderful journey to advance aggregate science — a research field dedicated to exploring the science beyond molecules. The past five years have witnessed the remarkable flourishing of this discipline, alongside the growing academic recognition of Aggregate. As we celebrate the 5-year anniversary, let us reflect on the past journey and envision the promising future (e70234).

This study presents a fimbriae-targeted SeVB⊃PQ complex for enhanced photodynamic therapy of periodontitis. The selenoviologen cyclophane host encapsulates a P. gingivalis-specific peptide, enabling precise bacterial binding and ROS generation upon light activation. This selective delivery enhances antimicrobial efficacy, restores subgingival microbiome homeostasis, and outperforms methylene blue in reducing inflammation and promoting tissue regeneration (e70159).