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Tert-butyl functional groups can modulate the self-assembly behavior of organic molecules on surfaces. However, the precise construction of supramolecular architectures through their controlled thermal removal remains a challenge. Herein, we precisely controlled the removal amount of tert-butyl groups in tetraazaperopyrene derivatives by stepwise annealing on Ag(111). The evolution of 4tBu-TAPP supramolecular self-assembly from the grid-like structure composed of 3tBu-TAPP through the honeycomb network formed by 2tBu-TAPP to the one-dimensional chain co-assembled by tBu-TAPP and TAPP was successfully realized. This series of supramolecular nanostructures were directly visualized by high resolution scanning tunneling microscopy. Tip manipulation and density functional theory calculations show that the formation of honeycomb network structure can be attributed to the van der Waals interactions, N–Ag–N coordination bonds, and weak C–H⋯N hydrogen bonds. Further addition of two tert-butyl groups (6tBu-TAPP) leads to a completely different assembly evolution, due to the fact that the additional tert-butyl groups affect the molecular adsorption behavior and ultimately induce desorption. This work can possibly be exploited in constructing stable and long-range ordered nanostructures in surface-assisted systems, which can also promote the development of nanostructures in functional molecular devices. [ABSTRACT FROM AUTHOR]

The semiconductor/insulator blends for organic field-effect transistors are a potential solution to improve the charge transport in the active layer by inducing phase separation in the blends. However, the technique is less investigated for long-chain conducting polymers such as Poly[2,5-(2-octyldodecyl)-3,6-diketopyrrolopyrrole-alt-5,5-(2,5-di(thien-2-yl)thieno [3,2-b]thiophene)] (DPPDTT), and lateral phase separation is generally reported due to the instability during solvent evaporation, which results in degraded device performance. Herein, we report how to tailor the dominant mechanism of phase separation in such blends and the molecular assembly of the polymer. For DPPDTT/PMMA blends, we found that for higher DPPDTT concentrations (more than 75%) where the vertical phase separation mechanism is dominant, PMMA assisted in the self-assembly of DPPDTT to form nanowires and micro-transport channels on top of PMMA. The formation of nanowires yielded 13 times higher mobility as compared to pristine devices. For blend ratios with DPPDTT ≤ 50%, both the competing mechanisms, vertical and lateral phase separation, are taking place. It resulted in somewhat lower charge carrier mobilities. Hence, our results show that by systematic tuning of the blend ratio, PMMA can act as an excellent binding material in long-chain polymers such as DPPDTT and produce vertically stratified and aligned structures to ensure high mobility devices. [ABSTRACT FROM AUTHOR]

Uncovering slow collective variables (CVs) of self-assembly dynamics is important to elucidate its numerous kinetic assembly pathways and drive the design of novel structures for advanced materials through the bottom-up approach. However, identifying the CVs for self-assembly presents several challenges. First, self-assembly systems often consist of identical monomers, and the feature representations should be invariant to permutations and rotational symmetries. Physical coordinates, such as aggregate size, lack high-resolution detail, while common geometric coordinates like pairwise distances are hindered by the permutation and rotational symmetry challenges. Second, self-assembly is usually a downhill process, and the trajectories often suffer from insufficient sampling of backward transitions that correspond to the dissociation of self-assembled structures. Popular dimensionality reduction methods, such as time-structure independent component analysis, impose detailed balance constraints, potentially obscuring the true dynamics of self-assembly. In this work, we employ GraphVAMPnets, which combines graph neural networks with a variational approach for Markovian process (VAMP) theory to identify the slow CVs of the self-assembly processes. First, GraphVAMPnets bears the advantages of graph neural networks, in which the graph embeddings can represent self-assembly structures in high-resolution while being invariant to permutations and rotational symmetries. Second, it is built upon VAMP theory, which studies Markov processes without forcing detailed balance constraints, which addresses the out-of-equilibrium challenge in the self-assembly process. We demonstrate GraphVAMPnets for identifying slow CVs of self-assembly kinetics in two systems: the aggregation of two hydrophobic molecules and the self-assembly of patchy particles. We expect that our GraphVAMPnets can be widely applied to molecular self-assembly. [ABSTRACT FROM AUTHOR]

Supramolecular gels are unique materials formed through the self-assembly of molecular building blocks, typically low molecular weight gelators (LMWGs), driven by non-covalent interactions. The process of crystallization within supramolecular gels has broadened the scope of the traditional gel-phase crystallization technique offering the possibility of obtaining crystals of higher quality and size. The broad structural diversity of LMWGs allows crystallization in multiple organic and aqueous solvents, favouring screening and optimization processes and the possibility to search for novel polymorphic forms. These supramolecular gels have been used for the crystallization of inorganic, small organic compounds of pharmaceutical interest, and proteins. Results have shown that these gels are not only able to produce crystals of high quality but also to influence polymorphism and physicochemical properties of the crystals, giving rise to crystals with potential new bio- and technological applications. Thus, understanding the principles of crystallization in supramolecular gels is essential for tailoring their properties and applications, ranging from drug delivery systems to composite crystals with tunable stability properties. In this review, we summarize the use of LMWG-based supramolecular gels as media to grow single crystals of a broad range of compounds. [ABSTRACT FROM AUTHOR]

A strategy for the screening and optimization of an artificial esterase is presented that utilizes the self‐assembly of amphiphilic molecules. Unlike conventional approaches that rely on the attachment of key functional groups onto molecular scaffolds or surfaces, the modular assembly of amphiphiles allows a large number of catalytic combinations to be investigated with minimal synthetic effort. In this study, iterative combinatorial screens led to an optimized esterase comprising amphiphiles that act as a nucleophilic catalyst, an oxyanion hole and a metal ion chelator. Cooperativity is observed between the functional headgroups of the amphiphiles, an effect that is diminished when co‐assembled with non‐functionalized surfactants. Assessment of the catalytic efficiency (kcat/KM) of our optimized catalysts against recently reported artificial esterases shows comparable efficiency, indicating that efficient catalysis is possible with dynamic self‐assembled systems despite the absence of pre‐defined rigid binding pockets. [ABSTRACT FROM AUTHOR]

Supramolecular polymers, as a type of dynamic polymers, are subordinate to the interdisciplinary field of polymer chemistry and supramolecular chemistry, whose development has greatly promoted the prosperity of new materials. Notably, molecular weight is one of the most important parameters of supramolecular polymers, which affects the physical/chemical properties and processing applications of materials. Developing new methods for characterizing the molecular weight of supramolecular polymers is crucial for advancing the development of supramolecular polymers. In this review, we elaborate and summarize three strategies for characterizing the molecular weight of supramolecular polymers that recently reported by our research group according to the characteristics of supramolecular polymers, including (1) the molecular weight distinction corresponding to variable fluorescence colors, (2) matching different molecular weights with different fluorescence lifetime, (3) transforming supramolecular polymers into mechanically interlocked polymers or covalent polymers. Besides, we also discuss the limitations of current methods for characterizing supramolecular polymers. We hope that this review can promote the development of supramolecular polymers and significantly inspire to exploit new methods to characterizing molecular weight of supramolecular polymers. [ABSTRACT FROM AUTHOR]

Multivalency is a fundamental principle in nature that leads to high‐affinity intermolecular recognition through multiple cooperative interactions that overcome the weak binding of individual constituents. For example, multivalency plays a critical role in lectin‐carbohydrate interactions that participate in many essential biological processes. Designing high‐affinity multivalent glycoconjugates that engage lectins results in systems with the potential to disrupt these biological processes, offering promising applications in therapeutic design and bioengineering. Here, a versatile and tunable synthetic platform for the synthesis of metallosupramolecular glycoassemblies is presented that leverages subcomponent self‐assembly, which employs metal ion templates to generate complex supramolecular architectures from simple precursors in one pot. Through ligand design, this approach provides precise control over molecular parameters such as size, shape, flexibility, valency, and charge, which afforded a diverse family of well‐defined hybrid glyconanoassemblies. Evaluation of these complexes as multivalent binders to Concanavalin A (Con A) by isothermal titration calorimetry (ITC) demonstrates the optimal saccharide tether length and the effect of electrostatics on protein affinity, revealing insights into the impact of synthetic design on molecular recognition. The presented studies offer an enhanced understanding of structure‐function relationships governing lectin‐saccharide interactions at the molecular level and guide a systematic approach towards optimizing glyconanoassembly binding parameters. [ABSTRACT FROM AUTHOR]

Living cells regulate the dynamics of developmental events through interconnected signaling systems that activate and deactivate inert precursors. This suggests that similarly, synthetic biomaterials could be designed to develop over time by using chemical reaction networks to regulate the availability of assembling components. Here we demonstrate how the sequential activation or deactivation of distinct DNA building blocks can be modularly coordinated to form distinct populations of self-assembling polymers using a transcriptional signaling cascade of synthetic genes. Our building blocks are DNA tiles that polymerize into nanotubes, and whose assembly can be controlled by RNA molecules produced by synthetic genes that target the tile interaction domains. To achieve different RNA production rates, we use a strategy based on promoter "nicking" and strand displacement. By changing the way the genes are cascaded and the RNA levels, we demonstrate that we can obtain spatially and temporally different outcomes in nanotube assembly, including random DNA polymers, block polymers, and as well as distinct autonomous formation and dissolution of distinct polymer populations. Our work demonstrates a way to construct autonomous supramolecular materials whose properties depend on the timing of molecular instructions for self-assembly, and can be immediately extended to a variety of other nucleic acid circuits and assemblies. DNA and RNA are the ideal building blocks to construct dynamic but programmable biomolecular materials. Here, the authors develop a modular system which allows the temporal control of filamentous DNA assemblies using cascaded gene networks. [ABSTRACT FROM AUTHOR]

Heterometallic supramolecules, known for their unique synergistic effects, have shown broad applications in photochemistry, host‐guest chemistry, and catalysis. However, there are great challenges to precisely construct heterometallic supramolecules rather than a statistical mixture, due to the limited metal‐ion selectivity of coordination units. In particular, heterometallic architectures precisely encoded with different metal ions usually fail to form in a one‐pot method when only one type of coordinated motif exists due to its poor metal‐ion selectivity. Herein, we propose an effective intramolecular cation‐π (ICπ) strategy and successfully constructed the heterometallic supramolecule Zn2Cu4L34 by the one‐pot self‐assembly of tritopic terpyridyl ligand L3 with Zn(II) and Cu(II), following a clear self‐assembly mechanism in which only thermodynamic dimers ZnL12 and Cu2L22 were constructed with model ligands L1, L2, Zn(II) and Cu(II) with perfect self‐sorting and an ultra‐high metal‐selectivity feature. The successful construction of the heterometallic supramolecule Zn2Cu4L34, in which the definite sequence of metal ions Zn(II) and Cu(II) is encoded in the one‐pot method, will offer a novel approach to precisely construct heterometallic architectures. [ABSTRACT FROM AUTHOR]

Knots containing metal atoms as part of their continuous strand backbone are termed as metallaknots. While several metallaknots have been synthesized through one-pot self-assembly, the designed synthesis of metallaknots by controlling the arrangement of entanglements and strands connectivity remains unexplored. Here, we report the synthesis of metallaknots composed with Au(I)-bis(acetylide) linkages and templated by Cu(I) ions. Varying the ratio of the building blocks results in the switchable formation of two trefoil knots with different stoichiometries and symmetries (C2 or D3) and an entangled metalla-complex. While the entangled complex formed serendipitously, the strand ends can be subsequently linked through coordinative closure to generate a 41 metallaknot in a highly designable fashion. The comparable structural characteristics of resulting metalla-complexes allow us to probe the correlations between their topologies and photophysical properties, showing the backbone rigidity of knots endows complexes with excellent phosphorescent properties. This strategy, in conjunction with the coordinative closure approach, provides a straightforward route for the formation of highly phosphorescent metallaknots that were previously challenging to access. [ABSTRACT FROM AUTHOR]

A yet‐outstanding supramolecular chemistry challenge is isolation of novel varieties of stacked complexes with finely‐tuned donor‐acceptor bonding and optoelectronic properties, as herein reported for binary adducts comprising two different cyclic trinuclear complexes (CTC@CTC'). Most previous attempts focused only on 1–2 factors among metal/ligand/substituent combinations, resulting in heterobimetallic complexes. Instead, here we show that, when all 3 factors are carefully considered, a broadened variety of CTC@CTC' stacked pairs with intuitively‐enhanced intertrimer coordinate‐covalent bonding strength and ligand‐ligand/metal‐ligand dispersion are attained (dM–M' 2.868(2) Å; ΔE>50 kcal/mol, an order of magnitude higher than aurophilic/metallophilic interactions). Significantly, CTC@CTC' pairs remain intact/strongly‐bound even in solution (Keq 4.67×105 L/mol via NMR/UV‐vis titrations), and the gas phase (mass spectrometry revealing molecular peaks for the entire CTC@CTC' units in sublimed samples), rather than simple co‐crystal formation. Photo‐/electro‐luminescence studies unravel metal‐centered phosphorescence useful for novel all metal‐organic light‐emitting diodes (MOLEDs) optoelectronic device concepts. This work manifests systematic design of supramolecular bonding and multi‐faceted spectral properties of pure metal‐organic macrometallacyclic donor/acceptor (inorganic/inorganic) stacks with remarkably‐rich optoelectronic properties akin to well‐established organic/organic and organic/inorganic analogues. [ABSTRACT FROM AUTHOR]

Enantiospecific effects play an uprising role in chemistry and technical applications. Chiral molecular networks formed by self‐assembly processes at surfaces can be imaged by scanning probe microscopy (SPM). Low contrast and high noise in the topography map often interfere with the automatic image analysis using classical methods. The long SPM image acquisition times restrain Artificial Intelligence‐based methods requiring large training sets, leaving only tedious manual work, inducing human‐dependent errors and biased labeling. By generating realistic looking synthetic images, the acquisition of real datasets is avoided. Two state‐of‐the‐art object detection architectures are trained to localize and classify chiral unit‐cells in a regular molecular chiral network formed by self‐assembly of linear molecular bricks. The comparison of different architectures and datasets demonstrates that the training on purely synthetic data outperforms models trained using augmented datasets. A Faster R‐CNN model trained solely on synthetic data achieved an excellent mean average precision of 99% on real data. Hence this approach and the transfer to real data show high success, also highlighting the high robustness against experimental noise and different zoom levels across the full experimentally reasonable parameter range. The generalizability of this idea is demonstrated by achieving equally high performance on a different structure, too. [ABSTRACT FROM AUTHOR]

The design of novel energetic compounds constitutes a pivotal research direction within the field of energetic materials. However, exploring the intricate relationship between their molecular structure and properties, in order to uncover their potential applications, remains a challenging endeavor. Therefore, employing multi-molecule assembly techniques to modulate the structure and performance of energetic materials holds immense significance. This approach enables the creation of a new generation of energetic materials, fueling research and development efforts in this field. In this study, a series of coordination compounds are synthesized by utilizing tetranitroethide (TNE) as an anion, which possesses a high nitrogen and oxygen content. The synthesis involves the synergistic modification between metal ions and small molecule ligands. Characterization of the obtained compounds is carried out using various techniques, including single crystal X-ray diffraction, IR spectroscopy, elemental analysis, and simultaneous TG–DSC analysis. Additionally, the energy of formation for these compounds is calculated using bomb calorimetry, based on the heat of combustion. The detonation performances of the compounds are determined through calculations using the EXPLO 5 software, and their sensitivities to external stimuli are evaluated. [ABSTRACT FROM AUTHOR]

Nature uses various chiral and unsymmetric building blocks to form substantial and complex supramolecular assemblies. In contrast, the majority of organic ligands used in metallosupramolecular chemistry are symmetric and achiral. Here we extend the group of unsymmetric chiral bile acids used as a scaffold for organic bispyridyl ligands by employing chenodeoxycholic acid (CDCA), an epimer of the previously used ursodeoxycholic acid (UDCA). The epimerism, flexibility, and bulkiness of the ligands leads to large structural differences in coordination products upon reaction with Pd(NO3)2. The UDCA‐bispyridyl ligand self‐assembles quantitatively into a single crown‐like Pd3L6 complex, whereas the CDCA ligand provides a mixture of coordination complexes of general formula PdnL2n, i.e., Pd2L4, Pd3L6, Pd4L8, Pd5L10, and even Pd6L12 containing an impressive 120 chiral centers. The coordination products were studied by a combination of analytical methods, with ion‐mobility mass spectrometry (IM‐MS) providing valuable details on their structure and allowed an effective separation of m/z 1461 to individual signals according to the arrival time distribution, thereby revealing four different ions of [Pd3L6(NO3)3]3+, [Pd4L8(NO3)4]4+, [Pd5L10(NO3)5]5+, and [Pd6L12(NO3)6]6+. The structures of all the complexes were modelled using DFT calculations. Finally, the challenges and conclusions in determining the specific structural identity of these unsymmetric species are discussed. [ABSTRACT FROM AUTHOR]

Surfactant molecules are known to self-assemble into micellar structures due to their amphiphilic nature of interactions with the solvent molecules. This ubiquitous phenomenon has been largely understood through the qualitative description of forces that govern these events. However, computational models that provide an accurate quantitative characterization of the process of micelle formation are still limited. In this study, we develop a coarse-grained computational model for Polysorbate 80 surfactant molecules that captures the phenomenon of aggregation at concentrations ranging from 0.1 % to 10 % in water. Here, we use a dissipative particle dynamics scheme to describe the interactions between the coarse-grained beads in the system. This computational model is able to reproduce the characteristics of micelle formation with increasing surfactant concentration. Our results demonstrate that despite loss in the degrees of freedom, the coarse-grained model predicts the structural and transport properties of the surfactant system with sufficient accuracy. The presented coarse-grained modeling technique offers a new window to uncover the molecular mechanisms of self-organization in the biophysical systems over a wide range of lengths and time scales. [ABSTRACT FROM AUTHOR]

Based on the principle of molecular design and self-assembly, a novel rare earth based arsenotungstate was obtained by introducing rare earth LaⅢ ions into the lacunary polyoxotungstates clusters with vacancy structure by one-pot method with Na2 WO4 ·2H2 O, NaAsO2 and LaCl3 ·6H2 O as the main materials. The structure and composition of this complex was confirmed by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), infrared spectroscopy (IR) and so on. The single crystal X-ray diffraction results show that the complex is in the monoclinic system, C2/c space group, and with the cell parameters of a =3.595 56(14) nm, b =1.222 48(4) nm, c =2.247 34(9) nm, β = 117.117 0(10)°, V =8.792 3(6) nm3, Z =4. The molecular formula of this compound is [(CH3)2 NH2]8 H3. 56 [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 } {AsW9 O33 }2]. And the polyoxoanion [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 }{AsW9 O33 }2]11. 56 - shows a novel sandwich type structure, which can be simply described as two trilacunary Keggin type{AsW9 O33 } units are linked by a {LaO(H2 O)2 } segment, a {WO(H2 O)} segment and a {W0. 24 (H2 O)2 } segment. Catalytic degradation property of this compound for Rhodamine-B was further inverstigated. The results demonstrate that the compound shows good photocatalytic activity under the condition of 300 W Hg lamp irradiation, and the degradation efficiency reaches to 74%. [ABSTRACT FROM AUTHOR]

Hypothesis. Multi-walled tubular aggregates formed by hierarchical self-assembly of beta-cyclodextrin (β -CD) and sodium dodecylsulfate (SDS) hold a great potential as microcarriers. However, the underlying mechanism for this self-assembly is not well understood. To advance the application of these structures, it is essential to fine-tune the cavity size and comprehensively elucidate the energetic balance driving their formation: the bending modulus versus the microscopic line tension. Experiments. We investigated temperature-induced changes in the hierarchical tubular aggregates using synchrotron small-angle X-ray scattering across a broad concentration range. Detailed analysis of the scattering patterns enabled us to determine the structural parameters of the microtubes and to construct a phase diagram of the system. Findings. The microtubes grow from the outside in and melt from the inside out. We relate derived structural parameters to enthalpic changes driving the self-assembly process on the molecular level in terms of their bending modulus and microscopic line tension. We find that the conformation of the crystalline bilayer affects the saturation concentration, providing an example of a phenomenon we call conformational freezing point depression. Inspired by the colligative phenomenon of freezing point depression, well known from undergraduate physics, we model this system by including the membrane conformation, which can describe the energetics of this hierarchical system and give access to microscopic properties without free parameters.   [ABSTRACT FROM AUTHOR]

The Pt/TaON/GLC prepared by in-situ molecular self-assembly strategy exhibits higher ORR activity and durability, since Janus structural TaON/GLC dual-carrier presents a maximum synergy for the improvement in conductivity, O 2 adsorption and O O cleavage. [Display omitted] • Janus TaON/GLC dual-carrier is prepared via an in-situ self-assembly strategy. • The Janus structure provides strong metal-carrier and carrier-carrier interactions. • Pt/TaON/GLC exhibits higher ORR activity and durability compared to Pt/C. • TaON and GLC present the maximum synergies during ORR process. Developing carbon-supported Pt-based electrocatalysts with high activity and long-durability for the oxygen reduction reaction (ORR) is an enormous challenge for their commercial applications due to the corrosion of carbon supports in acid/alkaline solution at high potential. In this work, a Janus structural TaON/graphene-like carbon (GLC) was synthesized via an in-situ molecular selfassembly strategy, which was used as a dual-carrier for platinum (Pt). The as-obtained Pt/TaON/GLC presents high half-wave potential (0.94 V vs. RHE), excellent mass (1.48 A mg Pt -1) and specific (1.75 mA cm Pt -2) activities at 0.9 V, and superior long-term durability with a minimal loss (8.0 %) of mass activity after 10,000 cycles in alkaline solution, outperforming those of Pt/C and other catalysts. The structural characterizations and density functional theory (DFT) calculations indicate that the Pt/TaON/GLC catalyst exhibits the maximum synergies, including enhanced interfacial electron density, improved charge transfer, enhanced O 2 adsorption, and superimposed O O cleavage. This work shows a potential strategy for preparing the high-active and long-durable Pt-based electrocatalyst by synergism-promoted interface engineering. [ABSTRACT FROM AUTHOR]

Mechanical energy, specifically in the form of ultrasound, can induce pressure variations and temperature fluctuations when applied to an aqueous media. These conditions can both positively and negatively affect protein complexes, consequently altering their stability, folding patterns, and self-assembling behavior. Despite much scientific progress, our current understanding of the effects of ultrasound on the self-assembly of amyloidogenic proteins remains limited. In the present study, we demonstrate that when the amplitude of the delivered ultrasonic energy is sufficiently low, it can induce refolding of specific motifs in protein monomers, which is sufficient for primary nucleation; this has been revealed by MD. These ultrasound-induced structural changes are initiated by pressure perturbations and are accelerated by a temperature factor. Furthermore, the prolonged action of low-amplitude ultrasound enables the elongation of amyloid protein nanofibrils directly from natively folded monomeric lysozyme protein, in a controlled manner, until it reaches a critical length. Using solution X-ray scattering, we determined that nanofibrillar assemblies, formed either under the action of sound or from natively fibrillated lysozyme, share identical structural characteristics. Thus, these results provide insights into the effects of ultrasound on fibrillar protein self-assembly and lay the foundation for the potential use of sound energy in protein chemistry. [ABSTRACT FROM AUTHOR]

Soft-matter-based photonic crystals like blue-phase liquid crystals (BPLC) have potential applications in wide-ranging photonic and bio-chemical systems. To date, however, there are limitations in the fabrication of large monocrystalline BPLCs. Traditional crystal-growth process involves the transition from a high-temperature disordered phase to an ordered (blue) phase and is generally slow (takes hours) with limited achievable lattice structures, and efforts to improve molecular alignment through post-crystallization field application typically prove ineffective. Here we report a systematic study on the molecular self-assembly dynamics of BPLC starting from a highly ordered phase in which all molecules are unidirectionally aligned by a strong electric field. We have discovered that, near the high-temperature end of the blue phase, if the applied field strength is then switched to an intermediate level or simply turned off, large-area monocrystalline BPLCs of various symmetries (tetragonal, orthorhombic, cubic) can be formed in minutes. Subsequent temperature tuning of the single crystal at a fixed applied field allows access to different lattice parameters and the formation of never-before-seen monoclinic structures. The formed crystals remain stable upon field removal. The diversity of stable monocrystalline BPLCs with widely tunable crystalline symmetries, band structures, and optical dispersions will significantly improve and expand their application potentials. Soft-matter-based photonic crystals like blue-phase liquid crystals (BPLC) have potential applications but face fabrication limitations for large monocrystalline structures. The authors report a method to rapidly form large-area monocrystalline BPLCs with various symmetries and tunable properties through an application of electric fields and temperature control. [ABSTRACT FROM AUTHOR]

To achieve the optimal alginate-based oral formulation for delivery of hydrophobic drugs, on the basis of previous research, we further optimized the synthesis process parameters of alginate-g-oleylamine derivatives (Ugi-FOlT) and explored the effects of different degrees of substitution (DSs) on the molecular self-assembly properties of Ugi-FOlT, as well as the in vitro cytotoxicity and drug release behavior of Ugi-FOlT. The resultant Ugi-FOlT exhibited good amphiphilic properties with the critical micelle concentration (CMC) ranging from 0.043 mg/mL to 0.091 mg/mL, which decreased with the increase in the DS of Ugi-FOlT. Furthermore, Ugi-FOlT was able to self-assemble into spherical micellar aggregates in aqueous solution, whose sizes and zeta potentials with various DSs measured by dynamic light scattering (DLS) were in the range of 653 ± 25~710 ± 40 nm and −58.2 ± 1.92~−48.9 ± 2.86 mV, respectively. In addition, RAW 264.7 macrophages were used for MTT assay to evaluate the in vitro cytotoxicity of Ugi-FOlT in the range of 100~500 μg/mL, and the results indicated good cytocompatibility for Ugi-FOlT. Ugi-FOlT micellar aggregates with favorable stability also showed a certain sustained and pH-responsive release behavior for the hydrophobic drug ibuprofen (IBU). Meanwhile, it is feasible to control the drug release rate by regulating the DS of Ugi-FOlT. The influence of different DSs on the properties of Ugi-FOlT is helpful to fully understand the relationship between the micromolecular structure of Ugi-FOlT and its macroscopic properties. [ABSTRACT FROM AUTHOR]

Nucleic acids (DNA and RNA) have been recognized as promising building blocks to fabricate a variety of well-defined two- and three-dimensional architectures through the programmable molecular self-assembly of multiple oligomeric strands. Y-shaped oligonucleotides are currently among the most widely employed nanostructures in the field of nucleic acid nanotechnology due to their unique features, including high structural stability, excellent biocompatibility, simplicity and ease of synthesis, and precisely controlled sizes. To functionalize biological activity, Y-shaped oligonucleotides can be incorporated with therapeutic genes such as small interfering RNA (siRNA) for target gene-specific silencing and CpG oligonucleotides (CpG ODN) for the activation of innate immune responses. Compared to the linear structures of siRNA and CpG ODN, Y-shaped siRNA and CpG ODN structures have demonstrated significant potential in the treatment of various diseases due to improved serum stability and intracellular uptake. Here, we review a broad spectrum of related topics, including the design, construction, and characteristics of Y-shaped oligonucleotides with a specific focus on their potential as a promising platform for enhancing the therapeutic efficacy of siRNA and CpG ODN. [ABSTRACT FROM AUTHOR]

Kagome lattices constitute versatile platforms for studying paradigmatic correlated phases. While molecular self-assembly of kagome structures on metallic substrates is promising, it is challenging to realize pristine kagome properties because of hybridization with the bulk degrees of freedom and modified electron-electron interactions. We suggest that a superconducting substrate offers an compelling platform for realizing a magnetic kagome lattice. Exchange coupling induces kagome-derived bands at the interface, which are protected from the bulk by the superconducting energy gap. We realize a magnetic kagome lattice on a superconductor by depositing Fe-porphin-chloride molecules on Pb(111) and using temperature-activated de-chlorination and self-assembly. This allows us to control the formation of smaller kagome precursors and long-range ordered kagome islands. Using scanning tunneling microscopy and spectroscopy at 1.6 K, we identify Yu-Shiba-Rusinov states inside the superconducting energy gap and track their hybridization from the precursors to larger islands, where the kagome lattice induces extended YSR bands. These YSR-derived kagome bands inside the superconducting energy gap allow for long-range coupling and induced pairing correlations, motivating further studies to resolve possible spin-liquid or Kondo-lattice-type behavior. Molecular self-assembly is a promising method for growing 2D kagome lattices. Here the authors report a kagome lattice of magnetic molecules on a superconducting surface and show the resulting magnetic bound states and their hybridization in the superconductor. [ABSTRACT FROM AUTHOR]

Metal-assisted molecular self-assembly finds applications in optoelectronics, chemical sensing and catalysis. In this article, fluorescein based polynorbornene is synthesized and its molecular self-assembly is used to detect the presence of copper(II) ions in environmental water samples (pond waters). First of all, the sequential procedures of the synthesis of norbornene and polynorbornene are accomplished using simple organic compounds available in the Indian market. Various intermediate compounds and norbornene are characterized by ¹H NMR and 13C NMR techniques. Structure of polynorbornene is proved by ¹H NMR spectroscope. Molecular weight of polynorbornene is obtained using Acquity advanced polymer chromatography. Particle size of polymer nano-aggregates is derived by using FESEM microscope. This polynorbornene (PNor-Flu) is used for the selective and sensitive detection of the copper(II) ions with an excellent LOD of 0.27 μM, far below the limit decided by the Environmental Protection Agency (EPA) of USA. This is achieved with the help of UV-Vis studies and spectroscopic titrations using OD416/OD350. As far the self-assembly is concerned using microscopic analysis, polynorbornene with a higher number of hydroxyl groups shows rod-like self-assembly. Polynorbornene structure is again transformed to a spherical shape in the presence of the copper(II) ions even in micromolar concentration. From this change, it is believed that the poynorbornene has a high potentiality for sensing the copper(II) ions, which helps it to impart unique morphological properties. From the tests performed on real water samples, polynorbornene has proved its high efficiency of selective and sensitive detective power for detecting copper(II) ions in pond waters. [ABSTRACT FROM AUTHOR]

Global changes and drug abuse are forcing humanity to face various disease problems, and alternative therapies with safe natural substances have important research value. This paper combines various techniques in quantum chemical calculations and molecular simulations to provide molecular-level insight into the dynamics of the self-assembly of N-isopropylacrylamide (NIPAM) for loading curcumin (CUR). The results indicate that increasing the chain length of NIPAM molecules reduces their efficiency in encapsulating and locking CUR, and electrostatic interactions and van der Waals interactions are the main driving forces behind the evolution of system configurations in these processes. The isopropyl groups of NIPAM and the two phenolic ring planes of CUR are the main contact areas for the interaction between the two types of molecules. The thermosensitive effect of NIPAM can alter the distribution of isopropyl groups in NIPAM molecules around CUR. As a result, when the temperature rises from ambient temperature (300 K) to human characteristic temperature (310 K), the NIPAM-CUR interactions and radial distribution functions suggest that body temperature is more suitable for drug release. Our findings offer a vital theoretical foundation and practical guidance for researchers to develop temperature-sensitive drug delivery systems tailored for CUR, addressing its clinical application bottleneck. Curcumin is a natural substance with beneficial pharmacological properties, but its poor solubility, instability and poor absorption hinder its use as a therapeutic agent in the body. Here, the authors use quantum chemical calculations and molecular simulations to explore the self-assembly of N-isopropylacrylamide for its use in the loading and release of curcumin. [ABSTRACT FROM AUTHOR]

The molecular structures of surfactants play a pivotal role in influencing their self‐assembly behaviors. In this work, using simulations and experiments, an unconventional hierarchically layered structure in the didodecyldimethylammonium bromide (DDAB)/water binary system: lamellae‐in‐lamellae is revealed, a new self‐assembly structure in surfactant system. This self‐assembly structure refers to a lamellar structure with a shorter periodic length (inner lamellae) embedded in a lamellar phase with a longer periodic length (outer lamellae). The normal vectors of these two lamellar regions orient perpendicularly. In addition, it is observed that this lamellar‐in‐lamellar phase disappears when the two tails of the cationic surfactants become longer. The formation of the lamellar‐in‐lamellar architecture arises from multiple interacting factors. The key element is that the short tails of the DDAB surfactants enhance hydrophilicity and rigidity, which facilitates the formation of the inner lamellae. Moreover, the lateral monolayer of the inner lamellae provides shielding from the water and prompts the formation of the outer lamellae. These findings indicate that molecular structures and flexibility can profoundly redirect the hierarchical self‐assembly behaviors in amphiphilic systems. More broadly, this work presents a new strategy to deliberately program hierarchical nanomaterials by designing specific surfactant molecules to act as tunable scaffolds, reactors, and carriers. [ABSTRACT FROM AUTHOR]

Carrier-free self-assembly has gradually shifted the focus of research on natural products, which effectively improve the bioavailability and the drug-loading rate. However, in spite of the existing studies, the development of self-assembled natural phytochemicals that possess pharmacological effects still has scope for further exploration and enhancement. Herein, a nano-delivery system was fabricated through the direct self-assembly of Rhein and Matrine and was identified as a self-assembled Rhein-Matrine nanoparticles (RM NPs). The morphology of RM NPs was characterized by TEM. The molecular mechanisms of self-assembly were explored using FT-IR, 1H NMR, and molecular dynamics simulation analysis. Gelatin methacryloyl (GelMA) hydrogel was used as a drug carrier for controlled release and targeted delivery of RM NPs. The potential wound repair properties of RM NPs were evaluated on a skin wound-healing model. TEM and dynamic light scattering study demonstrated that the RM NPs were close to spherical, and the average size was approximately 75 nm. 1H NMR of RM NPs demonstrated strong and weak changes in the interaction energies during self-assembly. Further molecular dynamics simulation analysis predicted the self-assembly behavior. An in vivo skin wound-healing model demonstrated that RM NPs present better protection effect against skin damages. Taken together, RM NPs are a new self-assembly system; this may provide new directions for natural product applications. [ABSTRACT FROM AUTHOR]

In a search to explore the structural landscape of possible copper(II) complexes with the 4-phenylimidazole/ tetrafluoroborate combination, considerable solvatomorphism has emerged. The utilization of a wide variety of crystallization solvents (polar protic, polar and non-polar aprotic) resulted in a series of seventeen crystalline solvatomorphs with the general formulae [Cu(BF4)2(HL)4]·x(solvent) [HL = 5-phenylimidazole, x(solvent) = 2(acetone)·2(water) (1), 2(methanol) (2), 2(ethanol) (3), 2(1-propanol) (4), 1.4(2-propanol) (5), 2(1-butanol) (6), 2(iso-butanol) (7), 1.33(tert-butanol) (8), 2(1-pentanol) (9), 2(dimethylformamide) (10), 1.2(acetone) (11), 2(tetrahydrofurane) (12), 1.85(1,4-dioxane) (13), 0.86(ethyl acetate) (14), 1(diethyl ether) (15), 0.7(diisopropyl ether) (16), 1(n-hexane) (17)]. A reaction using the CH2Cl2/MeCN solvent system produced crystals of the [Cu(HL)4(MeCN)(H2O)0.4](BF4)2 complex (18). Crystallization with nitromethane yielded [Cu{SiF2O(OMe)}2(HL)4]·0.8MeNO2 (19·0.8MeNO2), due to the in situ reaction of fluoride ions from BF4− ions with the glass surface of the vial used to grow crystals. The structures have been solved by single-crystal X-ray diffraction and the complexes were characterized by thermal analysis and infrared spectroscopy. The crystallization solvents are located in channels, with the exception of 1.33(tert-butanol) (8) and 1.2(acetone) (11) residing in lattice pockets. An analysis to understand the role of the solvents in the molecular self-assembly process is described. Depending on the hydrogen-bond functionalities of each solvent, three distinct cases emerge i) the solvents link neighboring [Cu(BF4)2(HL)4] molecules via N–H⋯Osolvent–H⋯F intermolecular associations (polar protic solvents, compounds 1–9), ii) they are terminally connected to [Cu(BF4)2(HL)4] molecules (polar aprotic solvents, compounds 10–13) and iii) they simply reside in channels without any involvement in supramolecular motifs (non-polar solvents, compounds 14–17). The final crystal packings result from the concerted action of robust N–H⋯F synthons and the above described interactions involving the solvent molecules. [ABSTRACT FROM AUTHOR]

Self‐assembling peptides have numerous applications in medicine, food chemistry, and nanotechnology. However, their discovery has traditionally been serendipitous rather than driven by rational design. Here, HydrogelFinder, a foundation model is developed for the rational design of self‐assembling peptides from scratch. This model explores the self‐assembly properties by molecular structure, leveraging 1,377 self‐assembling non‐peptidal small molecules to navigate chemical space and improve structural diversity. Utilizing HydrogelFinder, 111 peptide candidates are generated and synthesized 17 peptides, subsequently experimentally validating the self‐assembly and biophysical characteristics of nine peptides ranging from 1–10 amino acids—all achieved within a 19‐day workflow. Notably, the two de novo‐designed self‐assembling peptides demonstrated low cytotoxicity and biocompatibility, as confirmed by live/dead assays. This work highlights the capacity of HydrogelFinder to diversify the design of self‐assembling peptides through non‐peptidal small molecules, offering a powerful toolkit and paradigm for future peptide discovery endeavors. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO2) is a major pollutant that poses significant risks to sustainable human life. As a result, a growing focus has been placed on the development of highly selective and sensitive gas sensors for NO2. Traditional cutting-edge non-organic NO2 gas detectors often necessitate stringent production conditions and potentially harmful materials, which are not environmentally friendly, and these shortcomings have limited their widespread practical use. To overcome these challenges, we synthesized self-assembled peptide nanotubes (SPNTs) through a molecular self-assembly process. The SPNTs were then combined with SnO2 in varying proportions to construct NO2 gas sensors. The design of this sensor ensured efficient electron transfer and leverage the extensive surface area of the SPNTs for enhanced gas adsorption and the effective dispersion of SnO2 nanoparticles. Notably, the performance of the sensor, including its sensitivity, response time, and recovery rate, along with a lower detection threshold, could be finely tuned by varying the SPNTs content. This approach illustrated the potential of bioinspired methodologies, using peptide self-assemblies, to develop integrated sensors for pollutant detection, providing a significant development in environmentally conscious sensor technology. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL), as an important chiroptical phenomenon, can not only directly characterize excited-state structural information about chiroptical materials but also has great application prospects in 3D optical displays, information storage, biological probes, CPL lasers and so forth. Recently, chiral organic small molecules with CPL have attracted a lot of research interest because of their excellent luminescence efficiency, clear molecular structures, unique flexibility and easy functionalization. Planar chiral organic compounds make up an important class of chiral organic small molecular materials and often have rigid macrocyclic skeletons, which have important research value in the field of chiral supramolecular chemistry (e.g., chiral self-assembly and chiral host–guest chemistry). Therefore, research into planar chiral organic compounds has become a hotspot for CPL. It is time to summarize the recent developments in CPL-active compounds based on planar chirality. In this feature article, we summarize various types of CPL-active compounds based on planar chirality. Meanwhile, we overview recent research in the field of planar chiral CPL-active compounds in terms of optoelectronic devices, asymmetric catalysis, and chiroptical sensing. Finally, we discuss their future research prospects in the field of CPL-active materials. We hope that this review will be helpful to research work related to planar chiral luminescent materials and promote the development of chiral macrocyclic chemistry. [ABSTRACT FROM AUTHOR]

Repeated programmability has emerged as a desired property in smart device engineering, but the programmability will fatigue upon repeated applications due to the unmatched mechanical property between the layer materials and the polymeric glue that is required to integrate the two individual oriented layers. It is reported here that glue‐free antifatigue programmable laminate materials can be made with films resulted from solid‐phase molecular self‐assembly (SPMSA). The SPMSA films are created by squeezing the precipitates of oppositely charged polyelectrolytes and DTAB with a noodle machine, where the hydrophobic DTAB molecules self‐assembled into wormlike micelles and oriented along the squeezing direction. The surface molecules in this film are endowed with sufficient mobility in the presence of hydration water, so that two such films are able to be pressed into a laminate material owing to the hydrophobic and electrostatic interactions between the molecules on the two adjacent surfaces. As the water evaporated gradually, the left laminate materials are glue‐free with the same composition. When many of such films are integrated with specific designs, complicated shape programming is able to be achieved, and the programmability is reversible without fatigue. The current strategy is envisioned as a potent intriguing pathway leading to advanced programable materials. [ABSTRACT FROM AUTHOR]

In solid propellants, combustion catalysts play a crucial role. Here, we introduce a convenient method for the self-assembly of UIO-66 (Mn) in the presence of water, leading to the preparation of Mn/C aerogels. The aerogels were successfully utilized in the thermocatalytic decomposition of ammonium perchlorate (AP). The results indicate that the incorporation of 2% mass fraction of Mn/C aerogels enhances the peak temperature of AP decomposition by approximately 87.5°C. Mn/C aerogels demonstrate excellent catalytic performance. In combination with kinetics, we propose a thermal catalytic mechanism. [ABSTRACT FROM AUTHOR]

Electronic or nuclear spins represent promising candidates of qubits for applications in quantum information technologies and spintronic devices. However, it remains a challenge to achieve scalable and spatially defined organization of a large number of spins as qubits, which is essential in the feasible fabrication of quantum circuits. We report a strategy of block copolymer self‐assembly to organize molecular spins as qubits across molecular to micro‐/nano‐scales in polymeric films of organic luminescent radicals centered in star‐like block copolymers. We have achieved not only scalable and spatially defined organization of the molecular spins in polymeric films with long‐range periodic ordering but also controllable spin‐lattice relaxation dynamics and spin coherence lifetimes that can be finely tuned by the domain sizes and rigidities of the polymeric matrices. [ABSTRACT FROM AUTHOR]

The inclusion of colloidal particles into 3D porous constructs to realize heterostructure ensembles enhances surface interactions and energy transfer that can transform the catalytic properties of conventional catalysts. However, assembling hydrophobic colloidal nanoparticles within hydrophilic 3D porous matrices to create tailored heterostructures and catalytic properties is particularly challenging. Here, a modified ligand grafting method is presented to spontaneously assemble CdS inorganic colloidal quantum dots within a metal‐organic framework (MOF) derived porous framework for efficient photocatalytic CO2 reduction. The grafted long chain molecular ligands effectively suppress phase separation and endow a molecular‐recognition effect to form ordered assembly microstructures. The proof‐of‐concept assembly of CdS and Prussian blue analogues (PBA) derived Co3O4 facilitates a high density of heterojunctions formation, improving charge transfer and extended lifetimes of photo‐induced electrons. Consequently, CdS/Co3O4 assembly exhibits exceptionally active and stable photocatalytic CO2 reduction activity, with a CO production rate of 73.9 µmol g−1 h−1 and CO selectivity of 98.9%. Importantly, the ligand grafting method can be generalized to achieve spontaneous assembly of quantum dots within various metal organic framework derived porous scaffolds. This work provides a rational strategy for precise self‐assembly of colloidal nanoparticles within porous microstructures, allowing tailored heterointerfaces for functional materials and applications. [ABSTRACT FROM AUTHOR]

Hydrogen bonds are the fundamental factors stabilizing DNA and RNA macromolecules. Based on their base-pair sequences, DNA and RNA perform various biological functions. A key feature of these sequences is their linkage via hydrogen bonds. The hydrogen bonding between sugars and nucleobases in RNA sequences is one of the major reasons behind several mutagenic disorders that can cause numerous genomic instabilities, various genetic diseases, and RNA rearrangement problems. Chemists explore hydrogen bonding stability in nucleic acids, which is crucial for understanding molecular-level differentiations with potential applications in the early diagnosis of hereditary diseases. In this work, five types of coordination polymers of CMP and dCMP, {[Cd(CMP)(bpa)(H2O)3]·2H2O}n (1), {[Cd(dCMP)2(bpa) (H2O)2]·4H2O}n (2), {[Cd(azpy)(H2O)4](CMP)·3H2O}n (3), {[Cd(dCMP)2(azpy)(H2O)2]·4H2O}n (4), and {[Cd(CMP)(bpe)(H2O)3]·2H2O}n (5) (azpy = 4,4'-azopyridine, bpa = 1,2-bis(4-pyridyl)ethane, and bpe = 1,2-bis(4-pyridyl)ethylene), were designed and studied. All complexes were fully characterized by employing the single-crystal X-ray diffraction method. Complex 1 is a 2D coordination polymer, whereas complexes 2-5 are 1D coordination polymers. Significantly, a novel sugar-nucleobase hydrogen bonding interaction was discovered in complexes 1, 3, and 5 for the first time, thus introducing a new supramolecular interaction that can be used in self-assembly and molecular recognition. The chirality in the supramolecular assemblies of the five complexes was comprehensively analyzed using single-crystal and solid-state CD spectra. [ABSTRACT FROM AUTHOR]

• A comprehensive demonstration of how to characterize and understand the self-assembly behavior of amphiphilic molecules in solution-based parenteral drug products, including CMC determination by DOSY NMR. • An innovative use of computational tools and multiple orthogonal experimental techniques to inform robust drug product design, contribute to impurity control strategies and help enable rapid progression of an anti-infective parenteral drug product to the clinic. • A case study of lipophilic impurity solubilization by prodrug self-assembly that informs when impurities might precipitate, leading to undesired particulate matter formation, for example during dose administration or on stability. PF-07304814 is a water-soluble phosphate ester prodrug of a small molecule inhibitor for the SARS CoV-2 3CL protease designed for the treatment of COVID-19. The amphiphilicity and self-assembly behavior of the prodrug was investigated computationally and experimentally via multiple orthogonal techniques to better design formulations for intravenous infusion. The self-assembly of PF-07304814 into micellar structures enabled an increase in the solubility of lipophilic impurities by up to 1900x in clinically relevant formulations. The observed solubilization could help extend the drug product shelf-life and in use stability through inhibition of precipitation, without the need for solubilizing excipients. The work presented in this manuscript provides a roadmap for the characterization of prodrug self-assembly and highlights the potential for prodrug modifications to enhance solubility of both active ingredients and impurities and to extend drug product shelf-life. [ABSTRACT FROM AUTHOR]

The bottom-up fabrication of supramolecular and self-assembly on various substrates has become an extremely relevant goal to achieve prospects in the development of nanodevices for electronic circuitry or sensors. One of the branches of this field is the self-assembly of functional molecular components driven through non-covalent interactions on the surfaces, such as van der Waals (vdW) interactions, hydrogen bonding (HB), electrostatic interactions, etc., allowing the controlled design of nanostructures that can satisfy the requirements of nanoengineering concepts. In this context, non-covalent interactions present opportunities that have been previously explored in several molecular systems adsorbed on surfaces, primarily due to their highly directional nature which facilitates the formation of well-ordered structures. Herein, we review a series of research works by combining STM (scanning tunneling microscopy) with theoretical calculations, to reveal the processes used in the area of self-assembly driven by molecule Landers equipped with functional groups on the metallic surfaces. Combining these processes is necessary for researchers to advance the self-assembly of supramolecular architectures driven by multiple non-covalent interactions on solid surfaces. [ABSTRACT FROM AUTHOR]

Considering that the plasmonic properties of metallic nanoparticles (NPs) are strongly influenced by their dielectric environment, comprehension and manipulation of this interplay are crucial for the design and optimization of functional plasmonic systems. In this study, the plasmonic behavior of silver nanoparticles encapsulated in diverse copolymer dielectric environments was investigated, focusing on the analysis of the emerging localized surface plasmon resonances (LSPRs) through both experimental and theoretical approaches. Specifically, two series of nanostructured silver ultrathin films were deposited via magnetron sputtering on heated Corning Glass substrates at 330 °C and 420 °C, respectively, resulting in the formation of self-assembled NPs of various sizes and distributions. Subsequently, three different polymeric layers were spin-coated on top of the silver NPs. Optical and structural characterization were carried out by means of UV–Vis spectroscopy and atomic force microscopy, respectively. Rigorous Coupled Wave Analysis (RCWA) was employed to study the LSPRs theoretically. The polymeric environment consistently induced a red shift as well as various alterations in the LSPR amplitude, suggesting the potential tunability of the system. [ABSTRACT FROM AUTHOR]

It has been proved to be an effective route to efficiently ameliorate photocatalytic performance of catalysts via designing three-dimensional (3D) hierarchical nanostructures and constructing oxygen vacancies (VOs). However, controlling the self-assembly of organization into 3D hierarchical nanostructures while introducing VOs in photocatalysts remains a challenge. Herein, we reported an ethylene glycol (EG) mediated approach to craft 3D hydrangea-structure Bi2MoO6 with VOs for efficient photocatalytic degradation of tetracycline. Through manipulating the EG concentration during the fabrication process, the influence of EG concentration on the Bi2MoO6 structure was systematically investigated. EG could promote the self-assembly of Bi2MoO6 nanosheets to form a 3D hierarchical structure. Compared with 2D nanoplates, 3D hierarchical architecture enhanced the surface area and the amount of active sites of Bi2MoO6. In addition, the reduction effect of EG on metallic oxide enabled the generation of VOs in Bi2MoO6. The VOs adjusted the electronic structure of Bi2MoO6, which not only enhanced the light harvesting, but also facilitated the simultaneous utilization of photo-induced electrons and holes to form reactive oxygen species (·O2− and ·OH) for the efficient tetracycline decomposition. 3D Bi2MoO6 hydrangea with VOs achieved a 79.4% removal efficiency of tetracycline after 75 min. This work provides a simple yet robust EG-mediated strategy, which not only promotes the self-assembly of nano-catalysts into 3D hierarchical architectures, but also crafts tunable VOs for highly efficient photocatalysis. [ABSTRACT FROM AUTHOR]

The Spindle Assembly Abnormal Protein 6 (SAS-6) forms dimers, which then self-assemble into rings that are critical for the nine-fold symmetry of the centriole organelle. It has recently been shown experimentally that the self-assembly of SAS-6 rings is strongly facilitated on a surface, shifting the reaction equilibrium by four orders of magnitude compared to the bulk. Moreover, a fraction of non-canonical symmetries (i.e., different from nine) was observed. In order to understand which aspects of the system are relevant to ensure efficient self-assembly and selection of the nine-fold symmetry, we have performed Brownian dynamics computer simulation with patchy particles and then compared our results with the experimental ones. Adsorption onto the surface was simulated by a grand canonical Monte Carlo procedure and random sequential adsorption kinetics. Furthermore, self-assembly was described by Langevin equations with hydrodynamic mobility matrices. We find that as long as the interaction energies are weak, the assembly kinetics can be described well by coagulation-fragmentation equations in the reaction-limited approximation. By contrast, larger interaction energies lead to kinetic trapping and diffusion-limited assembly. We find that the selection of nine-fold symmetry requires a small value for the angular interaction range. These predictions are confirmed by the experimentally observed reaction constant and angle fluctuations. Overall, our simulations suggest that the SAS-6 system works at the crossover between a relatively weak binding energy that avoids kinetic trapping and a small angular range that favors the nine-fold symmetry. [ABSTRACT FROM AUTHOR]

The promise of self-assembly to enable the bottom-up formation of materials with prescribed architectures and functions has driven intensive efforts to uncover rational design principles for maximizing the yield of a target structure. Yet, despite many successful examples of self-assembly, ensuring kinetic accessibility of the target structure remains an unsolved problem in many systems. In particular, long-lived kinetic traps can result in assembly times that vastly exceed experimentally accessible timescales. One proposed solution is to design non-equilibrium assembly protocols in which system parameters change over time to avoid such kinetic traps. Here, we develop a framework to combine Markov state model (MSM) analysis with optimal control theory to compute a time-dependent protocol that maximizes the yield of the target structure at a finite time. We present an adjoint-based gradient descent method that, in conjunction with MSMs for a system as a function of its control parameters, enables efficiently optimizing the assembly protocol. We also describe an interpolation approach to significantly reduce the number of simulations required to construct the MSMs. We demonstrate our approach with two examples; a simple semi-analytic model for the folding of a polymer of colloidal particles, and a more complex model for capsid assembly. Our results show that optimizing time-dependent protocols can achieve significant improvements in the yields of selected structures, including equilibrium free energy minima, long-lived metastable structures, and transient states. [ABSTRACT FROM AUTHOR]

The preparation of two tri-iodide salts, C7H11N2+·I3−·0.5H2O (1) and (C2H5)4N+·I3− (2), synthesized by the slow diffusion method in solution, is reported. Their structures have been characterized by means of single-crystal X-ray diffraction. They consist of two different arrangements of tri-iodide ions, organized in a one-dimensional linear chain for 1 and in two-dimensional T-shaped sheets for 2, stabilized by 4-dimethylaminopyridinium and tetraethylammonium ligands. An asymmetry of the tri-iodide anions is observed in both structures, and is associated to the I⋯I halogen and hydrogen bonding interactions. The generation of the resulting supramolecular networks for these compounds was found to be driven by hydrogen-bond assisted self-assembly. The crystal structures of the two compounds were found to be supported essentially by H⋯I interactions between organic molecules and tri-iodide anions. For compound 2, an additionally stabilization by O⋯H/H⋯O interactions due to the presence of water molecules occurs. The dominant intermolecular interactions and their directionality have been examined by Hirshfeld surfaces and fingerprint analysis. Both compounds were characterized further by FT-IR and Raman spectroscopy, TGA/DTG and UV-visible absorption by means of thin film methods. The target compounds were also studied computationally using density functional theory (DFT) and time-dependent DFT (TD-DFT) approaches to explore their potential performances and to rationalize the experimental results. An electronic transition from 3σg to has been proven to dominate intramolecular charge transfer occurring for both 1 and 2. This electronic communication leads to an HOMO–LUMO energy gap of 4.208 eV for 1 and 4.255 eV for 2. [ABSTRACT FROM AUTHOR]

The molecular‐level scrutinization of on‐surface tiling garners considerable interest among scientists. Herein, we demonstrate molecular‐level heptagonal tiling using the self‐assembly of a heptagonal meta‐phenylene‐ethynylene macrocycle featuring 14 long alkoxy substituents at the liquid–graphite interface using scanning tunneling microscopy. This heptagonal macrocycle produces an antiparallel pattern at the 1‐phenyloctane–graphite interface through van der Waals interactions between the alkoxy chains. This pattern resembles the densely packed pattern of heptagonal tiles, albeit with variations in the orientations and spacing of heptagonal cores owing to intermolecular interactions between the alkoxy chains. Conversely, at the 1,2,4‐trichlorobenzene–graphite interface, the heptagonal molecule forms an oblique pattern composed of four independent molecular orientations. This phenomenon arises from core distortion induced by the coadsorption of the solvent molecules within the intrinsic macrocyclic pores. This study elucidates the design strategy – specifically, the choice of heptagonal molecular building block – for heptagonal tiling and fills a crucial gap in the field of two‐dimensional crystal engineering. [ABSTRACT FROM AUTHOR]

Highlights: Nanopesticides with minimizing carrier were prepared through prodrug molecular design and molecular self-assembly. Nanopesticides with minimizing carrier are expected to solve the environmental risks caused by the unrestricted introduction of nanomaterials. Future development and challenges of nanopesticides with minimizing carrier. The flourishing progress in nanotechnology offers boundless opportunities for agriculture, particularly in the realm of nanopesticides research and development. However, concerns have been raised regarding the human and environmental safety issues stemming from the unrestrained use of non-therapeutic nanomaterials in nanopesticides. It is also important to consider whether the current development strategy of nanopesticides based on nanocarriers can strike a balance between investment and return, and if the complex material composition genuinely improves the efficiency, safety, and circularity of nanopesticides. Herein, we introduced the concept of nanopesticides with minimizing carriers (NMC) prepared through prodrug design and molecular self-assembly emerging as practical tools to address the current limitations, and compared it with nanopesticides employing non-therapeutic nanomaterials as carriers (NNC). We further summarized the current development strategy of NMC and examined potential challenges in its preparation, performance, and production. Overall, we asserted that the development of NMC systems can serve as the innovative driving force catalyzing a green and efficient revolution in nanopesticides, offering a way out of the current predicament. [ABSTRACT FROM AUTHOR]

Organic photothermal materials have attracted increasing attention because of their structural diversity, flexibility, and compatibility. However, their energy conversion efficiency is limited owing to the narrow absorption spectrum, strong reflection/transmittance, and insufficient nonradiative decay. In this study, two quinoxaline‐based D–A‐D–A‐D‐type molecules with ethyl (BQE) or carboxylate (BQC) substituents were synthesized. Strong intramolecular charge transfer provided both molecules with a broad absorption range of 350–1000 nm. In addition, the high reorganization energy and weak molecular packing of BQE resulted in efficient nonradiative decay. More importantly, the self‐assembly of BQE leads to a textured surface and enhances the light‐trapping efficiency with significantly reduced light reflection/transmittance. Consequently, BQE achieved an impressive solar‐thermal conversion efficiency of 18.16 % under 1.0 kW m−2 irradiation with good photobleaching resistance. Based on this knowledge, the water evaporation rate of 1.2 kg m−2 h−1 was attained for the BQE‐based interfacial evaporation device with an efficiency of 83 % under 1.0 kW m−2 simulated sunlight. Finally, the synergetic integration of solar‐steam and thermoelectric co‐generation devices based on BQE was realized without significantly sacrificing solar‐steam efficiency. This underscores the practical applications of BQE‐based technology in effectively harnessing photothermal energy. This study provides new insights into the molecular design for enhancing light‐trapping management by molecular self‐assembly, paving the way for photothermal‐driven applications of organic photothermal materials. [ABSTRACT FROM AUTHOR]

Hierarchical self‐assembly from simple building blocks to complex polymers is a feasible approach to constructing multi‐functional smart materials. However, the polymerization process of polymers often involves challenges such as the design of building blocks and the drive of external energy. Here, a hierarchical self‐assembly with self‐driven and energy conversion capabilities based on p‐aminophenol and diethylenetriamine building blocks is reported. Through β‐galactosidase (β‐Gal) specific activation to the self‐assembly, the intelligent assemblies (oligomer and superpolymer) with excellent photothermal and fluorescent properties are dynamically formed in situ, and thus the sensitive multi‐mode detection of β‐Gal activity is realized. Based on the overexpression of β‐Gal in ovarian cancer cells, the self‐assembly superpolymer is specifically generated in SKOV‐3 cells to achieve fluorescence imaging. The photothermal therapeutic ability of the self‐assembly oligomer (synthesized in vitro) is evaluated by a subcutaneous ovarian cancer model, showing satisfactory anti‐tumor effects. This work expands the construction of intelligent assemblies through the self‐driven cascade assembly of small molecules and provides new methods for the diagnosis and treatment of ovarian cancer. [ABSTRACT FROM AUTHOR]

Supramolecular hydrogels based on low-molecular-weight compounds are a unique class of so-called "soft" materials, formed by weak non-covalent interactions between precursors at their millimolar concentrations. Due to the variety of structures that can be formed using different low-molecular-weight gelators, they are widely used in various fields of technology and medicine. In this study, we report for the first time an unusual self-assembly process of mixing a hydrosol obtained from L-cysteine and silver nitrate (cysteine–silver sol—CSS) with sodium halides. Modern instrumental techniques such as viscosimetry, UV spectroscopy, dynamic light scattering, zeta potential measurements, SEM and EDS identified that adding fluoride anions to CSS is able to form stable hydrogels of a thixotropic nature, while Cl−, Br− and I− lead to precipitation. The self-assembly process proceeds using a narrow concentration range of F−. An increase in the fluoride anion content in the system leads to a change in the gel network morphology from elongated structures to spherical ones. This fact is reflected in a decrease in the gel viscosity and a number of gel–sol–gel transition cycles. The mechanism of F−'s interaction with hydrosol includes the condensation of anions on the positive surface of the CSS nanoparticles, their binding via electrostatic forces and the formation of a resulting gel carcass. In vitro analysis showed that the hydrogels suppressed human squamous carcinoma cells at a micromolar sample concentration. The obtained soft gels could have potential applications against cutaneous malignancy and as carriers for fluoride anion and other bioactive substance delivery. [ABSTRACT FROM AUTHOR]

The creation of polymer composite materials by compositing fillers into polymer materials is an effective method of improving the properties of polymer materials, and the development of new fillers and their novel composite methods is expected to lead to the creation of new polymer composite materials. In this study, we develop a new filler material made of low-molecular-weight gelators by applying a gelation process that simultaneously performs the swelling (gelation) of crosslinked polymer materials and the self-assembly of low-molecular-weight gelators into low-dimensional crystals in organic solvents within polymer materials. The gelation process of crosslinking rubber-based polymers using alkylhydrazides/toluene as the low-molecular-weight gelator allowed us to composite self-assembled sheet-like crystals of alkylhydrazides as fillers in polymeric materials, as suggested by various microscopic observations, including infrared absorption measurements, small-angle X-ray diffraction measurements and thermal analysis, microscopy, and infrared absorption measurements. Furthermore, tensile tests of the composite materials demonstrated that the presence of fillers improved both the Young's modulus and the tensile strength, as well as the elongation at yield. Additionally, heat treatment was shown to facilitate filler dispersion and enhance the mechanical properties. The findings demonstrate the potential of self-assembled sheet-like crystals of low-molecular-weight gelators as novel filler materials for polymers. The study's composite method utilizing gelators via gelation proved effective. [ABSTRACT FROM AUTHOR]

With many merits such as facile synthesis, economy, and relatively high theoretical capacity, Prussian blue analogs (PBAs) are considered promising cathode materials for sodium-ion batteries (SIBs). However, their practical applications still suffer from a low actual specific capacity and inferior stability owing to the imperfect crystallinity, irreversible phase transition, and low intrinsic conductivity. Herein, a surface-modification technique for vapor-phase molecular self-assembly was developed to prepare Fe-based PBAs, specifically sodium iron hexacyanoferrate (NaFeHCF), with a uniform conductive polymer protective layer of polypyrrole (PPy) on the surface, resulting in NaFeHCF@PPy. The incorporation of a PPy protective layer not only improves the electronic conductivity of NaFeHCF@PPy, but also effectively mitigates the dissolution of Fe-ions during cycling. Specifically, this advanced vapor-phase technique avoids Fe2+ oxidation and Na+ loss during liquid-phase surface modification. The NaFeHCF@PPy exhibited a remarkably enhanced cycling performance, with capacity retentions of 85.6% and 69.1% over 500 and 1000 cycles, respectively, at 200 mA/g, along with a superior rate performance up to 5 A/g (fast kinetics). Additionally, by adopting this strategy for Mn-based PBAs (NaMnHCF@PPy), we further demonstrated the universality of this method for PBA cathodes in SIBs. [ABSTRACT FROM AUTHOR]