Self-assembly Characteristics Research Articles

Metal-halide porous framework superlattices.

The construction of superlattices with a spatial modulation of chemical compositions allows for the creation of artificial materials with tailorable periodic potential landscapes and tunable electronic and optical properties1-5. Conventional semiconductor superlattices with designable potential modulation in one dimension has enabled high-electron-mobility transistors and quantum-cascade lasers. More recently, a diverse set of superlattices has been constructed through self-assembly or guided assembly of multiscale building units, including zero-dimensional nanoclusters and nanoparticles6,7, one-dimensional nanorods and nanowires8,9, two-dimensional nanolayers and nanosheets10-13, and hybrid two-dimensional molecular assemblies14-17. These self-assembled superlattices feature periodic structural modulation in two or three dimensions, but often lack atomic precision owing to the inevitable structural disorder at the interfaces between the constituent units. Here we report a one-pot synthesis of multi-dimensional single-crystalline superlattices consisting of periodic arrangement of zero-, one- and two-dimensional building units. By exploiting zirconium (IV) metal-organic frameworks as host templates for directed nucleation and precise growth of metal-halide sublattices through a coordination-assisted assembly strategy, we synthesize a family of single-crystalline porous superlattices. Single-crystal X-ray crystallography and high-resolution transmission electron microscopy clearly resolve the high-order superlattice structure with deterministic atomic coordinates. Further treatment with selected amine molecules produces perovskite-like superlattices with highly tunable photoluminescence and chiroptical properties. Our study creates a platform of high-order single-crystalline porous superlattices, opening opportunities to tailor the electronic, optical and quantum properties beyond the reach of conventional crystalline solids.

Preparation of Zwitterionic Sulfobetaines and Study of Their Thermal Properties and Nanostructured Self-Assembling Features.

Zwitterionic polymers have garnered significant attention for their distinctive properties, such as biocompatibility, antifouling capabilities, and resistance to protein adsorption, making them promising candidates for a wide range of applications, including drug delivery, oil production inhibitors, and water purification membranes. This study reports the synthesis and characterization of zwitterionic monomers and polymers through the modification of linear, vinyl, and aromatic heterocyclic functional groups via reaction with 1,3-propanesultone. Four zwitterionic polymers with varying molecular structures-ranging from linear to five and six membered ring systems-were synthesized: poly(sulfobetaine methacrylamide) (pSBMAm), poly(sulfobetaine-1-vinylimidazole) (pSB1VI), poly(sulfobetaine-2-vinylpyridine) (pSB2VP), and poly(sulfobetaine-4-vinylpyridine) (pSB4VP). Their molecular weights, thermal behavior, and self-assembly properties were analyzed using gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and zeta potential measurements. The glass transition temperatures (Tg) ranged from 276.52 °C for pSBMAm to 313.69 °C for pSB4VP, while decomposition temperatures exhibited a similar trend, with pSBMAm degrading at 301.03 °C and pSB4VP at 387.14 °C. The polymers' self-assembly behavior was strongly dependent on pH and their surface charge, particularly under varying pH conditions: spherical micelles were observed at neutral pH, while fractal aggregates formed at basic pH. These results demonstrate that precise modifications of the chemical structure, specifically in the linear, imidazole, and pyridine moieties, enable fine control over the thermal properties and self-assembly behavior of polyzwitterions. Such insights are essential for tailoring polymer properties for targeted applications in filtration membranes, drug delivery systems, and solid polymer electrolytes, where thermal stability and self-assembly play crucial roles.

Supramolecular multiplexes from collagen mimetic peptide-PNA(GGG)3 conjugates and C-rich DNA: pH-induced reversible switching from triplex-duplex to triplex-i-motif.

Peptides are well known for forming nanoparticles, while DNA duplexes, triplexes and tetraplexes create rigid nanostructures. Accordingly, the covalent conjugation of peptides to DNA/RNA produces hybrid self-assembling features and may lead to interesting nano-assemblies distinct from those of their individual components. Herein, we report the preparation of a collagen mimetic peptide incorporating lysine in its backbone, with alkylamino side chains radially conjugated with G-rich PNA [collagen-(PNA-GGG)3]. In the presence of complementary C-rich DNA (dCCCTTTCCC) at neutral pH, the collagen mimetic triplexes were interconnected by PNA-GGG : DNA-CCC duplexes, leading to the formation of larger assemblies of nanostructures. Upon decreasing the pH to 4.5, the dissociation of the triplex-duplex assembly released the protonated C-rich DNA, which immediately folded into an i-motif. With an increase in the pH to 7.2 (neutral), the i-motif unfolded into linear DNA, which reformed the PNA-GGG : DNA-CCC duplex interconnecting the collagen triplexes. The pH-induced switching of the assembly and disassembly was reversible over a few cycles. The hybrid collagen-(PNAGGG)3 : DNA-C3T3C3 triplex-duplex and the individual components of the assembly including the i-motif were characterized by UV and CD melting, fluorescence, TEM and gel electrophoresis. The pH-induced reversible switching was established by the changes in the CD and fluorescence properties. Peptide-DNA conjugates have wide applications in both biology and materials science, ranging from therapeutics and drug delivery to diagnostics and molecular switches. Thus, the prototype ensemble of the triplex peptide-PNA conjugate and its duplex with DNA described herein has potential for elaboration into rationally designed systems by varying the PNA/DNA sequences to trap functional ligands/drugs for release in pH-controlled environments.

(Invited) air/Liquid Interfacial Formation Process of Electrically Conductive Metal-Organic Framework Nanosheets

Development of rational methods for creating ordered two-dimensional (2D) structures with nanometer scale precision is one of the central issues in the nanoscience and nanotechnology fields because of their intrinsic physical-chemical properties which are seen in those of their equivalent bulk state. Inclusion of highly regulated nanopores into the nanosheet structure will further open the possible applications such as nanosieves, molecular/ion storage and sensor devices as well as introducing guest molecules into the nanopores tune variedly the sheet properties (electric conduction, nanoheterojunction). Utilizing molecular building units are suitable for creating such porous nanosheets because of rich variety of design and facile modification of size and shape.Here, I present a facile bottom-up synthesis of molecular nanosheets with both positional and size regulated nanopores utilizing air/liquid interfaces[1-5]. By applying liquid interfaces, growth direction of the object can be well controlled with utilizing self-assembly feature of the molecules under mild conditions. We have succeeded to tune finely the nanosheet structures by rational modification of molecular building units . The highly crystalline structure remains after transferring a solid substrate from the liquid surface as well as without any supports. Notably, such highly oriented porous crystalline structure is obtained specifically by applying bottom up synthesis at air/liquid interfaces, not by other techniques.I also present detailed insights into the formation process of electrically conductive MOF nanosheets composed of 2,3,6,7,10,11-hexaiminotriphenylene (HITP) and Ni(II) ions (HITP-Ni-NS) at the air/liquid interface [6-8]. The morphological and structural features of HITP-Ni-NS strongly depend on the standing time—the time without any external actions involved, but leaving the interface undisturbed after setting the ligand solution onto the metal-ion solution. We find that the fundamental features of HITP-Ni-NS are determined by the standing time with conductivity sensitively influenced by such pre-determined HITP-Ni-NS characteristics. These findings will lead towards the establishment of a rational strategy for creating MOF nanosheets at the air/liquid interface with desired properties, thereby accelerating their use in diverse potential applications.1. R. Makiura et al. Nature Mater. 9, 565 (2010).2. S. Motoyama, R. Makiura, O. Sakata, H. Kitagawa, J. Am. Chem. Soc. 133, 5640 (2011).3. R. Makiura, O. Konovalov, Sci. Rep. 3, 2506 (2013).4. R. Makiura et al. ACS Nano, 11, 10875–10882 (2017).5. R. Makiura et al, Coord. Chem. Rev. 469, 214650 (2022).6. R. Makiura et al, ACS Appl. Mater. Interfaces, 13, 54570 (2021).7. R. Makiura et al, J. Colloid Interface Sci. 651, 769 (2023).8. R. Makiura et al, Langmuir. 39, 8952 (2023). Figure 1

Coassembly of Charged Copolymer Amphiphiles Featuring pH-Regulated Antifouling Properties.

Understanding the formation of highly ordered structures through self-assembly is crucial for developing various biologically relevant systems. A significant expansion in the development of self-assembly chemistry features stable coassembly formation using a mixture of two oppositely charged polymers. This study provides insightful findings on the coassembly of hydrophobic coumarin-integrated cationic (P1-P3) and anionic (P1'-P3') copolymers toward the formation of vesicles in aqueous medium at pH 7.4, with a hydrodynamic diameter (Dh) of 160 ± 10 nm and electrically neutral zwitterionic surfaces, confirmed by dynamic light scattering. Upon varying the solution pH, an intriguing charge switchable behavior (+ve → 0 → -ve) and a drastic morphological transition to spherical aggregates of the vesicles were noticed. At pH 7.4, these coassembled vesicles possess a neutral surface charge, empowering them to resist nonspecific protein (pepsin and lysozyme) adsorption via electrostatic repulsion, as evidenced by size evolution and protein binding measurements. Additionally, the bilayer membrane allows for the encapsulation of hydrophilic and hydrophobic guest molecules and their sustained release in the presence of 10 mM esterase; thus, this study demonstrates potential applications of coassembly to serve as a drug delivery vehicle.

Pioneering SubPc-Br/CdS S-scheme heterojunctions: Achieving superior photocatalytic oxidation through enhanced radical synergy and photocorrosion mitigation

For the efficient harnessing of solar energy and mitigation of environmental pollution, the development and application of semiconductor photocatalysis technology is paramount. Herein, a novel SubPc-Br/CdS supramolecular array with an S-scheme heterojunction was synthesized through the intermolecular π-stacked self-assembly of subphthalocyanine (SubPc-Br) and nanometer cadmium sulfide (CdS). This self-assembly system features a highly structured architecture and excellent stability. Experiments and ground-state differential charge calculations demonstrate that SubPc-Br and CdS form a built-in electric field during the self-assembly process, a critical factor in promoting the dissociation of electrons and holes. Additionally, this study utilized time-dependent density functional theory (TDDFT) to simulate the dynamic adsorption behavior of excited oxygen molecules on the SubPc-Br/CdS interface for the first time. The analysis of molecular charge differential density under different excited states proved that the addition of SubPc-Br molecules not only improves the photocorrosion resistance of CdS in an O2 adsorption environment but also enhances the production of advanced reactive oxygen species under the synergistic action of h+ and ·O2–. When subjected to visible light, the degradation efficiency of minocycline (MC) achieved 96.8% within 60 min and maintained 80.3% after 5 cycles. In summary, this study highlights the feasibility of creating advanced S-scheme heterojunction photocatalysts through the strategic incorporation of organic supramolecules with semiconductor catalysts.

Electrically conductive and antimicrobial Pluronic-based hydrogels

Electrically conductive hydrogels (ECHs) combine the electrical properties of conductive materials with the unique features of hydrogels. They are attractive for various biomedical applications due to their smart response to electrical fields. Owing to their distinctive properties, such as biocompatibility, thermosensitivity and self-assembling behaviour, Pluronics can be adopted for the generation of hydrogels for biomedical applications. Here, innovative self-assembling ECHs holding antimicrobial properties for biomedical applications are developed, providing a full characterization of their macroscopic and microscopic properties. The rheological, morphological, and structural properties of Pluronic F68 (PF68) in the presence of conductive poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) (PEDOT:PSS) are studied to optimize the synthesis of novel biocompatible and electrically conductive hydrogels. The addition of silver (Ag) flakes to the aqueous samples of PF68/PEDOT:PSS is used to further enhance the systems electrical conductivity and antimicrobial potency. Aqueous optimal samples with 45 wt% PF68 and different PEDOT:PSS/silver contents are investigated by means of experimental rheology and small-angle X-ray scattering (SAXS), to unveil the influence of both PEDOT:PSS and silver on the phase diagram, macroscopic flow properties, and morphology of the Pluronic-based systems.The presence of PEDOT:PSS and silver flakes endows Pluronic systems with high conductive properties, while preserving the same self-assembly features of PF68 in water. Moreover, the functionalisation with silver flakes confers antimicrobial properties to the ECHs, as demonstrated by growth inhibition of the multi-drug resistant bacterium Staphylococcus aureus.The use of PF68 in this work provides a novel route for the synthesis of innovative ECHs, whose functionalities such as self-assembling behaviour, biocompatibility, conductivity, and bioactivity may inspire future avenues in the biomedical field.

Fine Structural Analysis of Degummed Fibroin Fibers Reveals Its Superior Mechanical Capabilities.

Bombyx mori silk fibroin fibers constitute a class of protein building blocks capable of functionalization and reprocessing into various material formats. The properties of these fibers are typically affected by the intense thermal treatments needed to remove the sericin gum coating layer. Additionally, their mechanical characteristics are often misinterpreted by assuming the asymmetrical cross-sectional area (CSA) as a perfect circle. The thermal treatments impact not only the mechanics of the degummed fibroin fibers, but also the structural configuration of the resolubilized protein, thereby limiting the performance of the resulting silk-based materials. To mitigate these limitations, we explored varying alkali conditions at low temperatures for surface treatment, effectively removing the sericin gum layer while preserving the molecular structure of the fibroin protein, thus, maintaining the hierarchical integrity of the exposed fibroin microfiber core. The precise determination of the initial CSA of the asymmetrical silk fibers led to a comprehensive analysis of their mechanical properties. Our findings indicate that the alkali surface treatment raised the Young's modulus and tensile strength, by increasing the extent of the fibers' crystallinity, by approximately 40 % and 50 %, respectively, without compromising their strain. Furthermore, we have shown that this treatment facilitated further production of high-purity soluble silk protein with rheological and self-assembly characteristics comparable to those of native silk feedstock, initially stored in the animal's silk gland. The developed approaches benefits both the development of silk-based materials with tailored properties and the proper mechanical characterization of asymmetrical fibrous biological materials made of natural building blocks.

Enhancing ion conductivity in polyethylene oxide-based polymers through semi-interpenetrating networks with liquid crystalline polymer for lithium metal batteries

Solid electrolytes play a pivotal role in these batteries but are hindered by challenges such as low ion conductivity and inadequate mechanical properties. In this study, a synergistic multi-component system was fabricated using a microphase separation technique to integrate liquid crystal polymers with self-assembly characteristics and polyethylene oxide (PEO) known for its excellent ion transport performance. Molecular-level control was achieved by adjusting the ratio of liquid crystal monomers, facilitating the construction of ordered ion transport pathways that significantly enhance room temperature ion transport efficiency. The resulting solid polymer electrolyte adopts a semi-interpenetrating network structure, where the rigid framework of liquid crystalline polymers is interpenetrated with flexible PEO chains. It exhibits a high room-temperature ion conductivity of 4.7 × 10−4 S/cm and a lithium-ion migration number of 0.71. Benefitting from its tailored microstructure and mechanical properties, the assembled lithium symmetric battery demonstrated stable operation over 2800 h at a room temperature current density of 0.1 mA/cm−2. This research presents a promising pathway for the advancement of advanced electrolyte materials, providing valuable insights into improving the efficiency and safety of lithium metal batteries in practical applications.

Synthesis and Characterization of Baicalein-loaded Aquasomes: An In vitro and In silico Perspective for Diabetes Mellitus.

Millions of individuals worldwide suffer from metabolic abnormalities induced by diabetes. Baicalein, a flavonoid, has shown several properties in various treatments with potential properties, including anti-inflammatory, antioxidant, and anti-diabetic properties. Practically, its application is hindered due to low solubility in aqueous media. Overcoming this challenge, aquasomes can offer an effective approach for delivering drugs and bioactive molecules to target various diseases. The study aimed to develop and evaluate baicalein-loaded aquasomes for improving solubility and comparing their antidiabetic properties to acarbose through in silico docking. Baicalein-loaded aquasomes were prepared through a three-step process: core preparation, lactose coating, and drug loading. The evaluation included assessing particle size, drug-excipient interactions, drug entrapment efficiency, loading capacity, in vitro drug release, and the kinetics of drug release. In silico docking and in vitro α-amylase inhibition activity was evaluated to assess the anti-diabetic potential of baicalein. The baicalein-loaded aquasomes were spherical with sizes ranging from 300-400 nm. FTIR analysis indicated no interaction between the components. The formulation exhibited drug entrapment efficiency of 94.04±0 4.01% and drug loading of 17.60 ± 01.03%. Drug release study showed sustained and complete (97.30 ± 02.06%) release, following first-order kinetics. Docking analysis revealed comparable binding affinity to acarbose, while the α-amylase inhibition assay showed greater inhibition potential of the aquasomes compared to the baicalein solution. Aquasomes offer an alternative approach to conventional delivery methods. The selfassembling characteristics of aquasomes greatly simplify their preparation process, adding to their appeal as a drug delivery system.

Recent Advances in Efficient Lutein-Loaded Zein-Based Solid Nano-Delivery Systems: Establishment, Structural Characterization, and Functional Properties.

Plant proteins have gained significant attention over animal proteins due to their low carbon footprint, balanced nutrition, and high sustainability. These attributes make plant protein nanocarriers promising for applications in drug delivery, nutraceuticals, functional foods, and other areas. Zein, a major by-product of corn starch processing, is inexpensive and widely available. Its unique self-assembly characteristics have led to its extensive use in various food and drug systems. Zein's functional tunability allows for excellent performance in loading and transporting bioactive substances. Lutein offers numerous bioactive functions, such as antioxidant and vision protection, but suffers from poor chemical stability and low bioavailability. Nano-embedding technology can construct various zein-loaded lutein nanodelivery systems to address these issues. This review provides an overview of recent advances in the construction of zein-loaded lutein nanosystems. It discusses the fundamental properties of these systems; systematically introduces preparation techniques, structural characterization, and functional properties; and analyzes and predicts the target-controlled release and bioaccessibility of zein-loaded lutein nanosystems. The interactions and synergistic effects between Zein and lutein in the nanocomplexes are examined to elucidate the formation mechanism and conformational relationship of zein-lutein nanoparticles. The physical and chemical properties of Zein are closely related to the molecular structure. Zein and its modified products can encapsulate and protect lutein through various methods, creating more stable and efficient zein-loaded lutein nanosystems. Additionally, embedding lutein in Zein and its derivatives enhances lutein's digestive stability, solubility, antioxidant properties, and overall bioavailability.

Novel Antioxidant Self-Assembled Peptides Extracted from Azumapecten farreri Meat: In Vitro- and In Silico-Assisted Identification.

Previous studies have found that the self-assembled supramolecules of Azumapecten farreri meat peptides have antioxidant effects. Therefore, this study aims to isolate and identify novel antioxidant peptides with self-assembly characteristics and analyze their structure-activity relationship through molecular docking and molecular dynamics simulation. The in vitro results show that as the purification steps increased, the antioxidant activity of peptides became stronger. Additionally, the purification step did not affect its pH-responsive self-assembly. Using LC-MS/MS, 298 peptide sequences were identified from the purified fraction PF1, and 12 safe and antioxidant-active peptides were acquired through in silico screening. The molecular docking results show that they had good binding interactions with key antioxidant-related protein ligands (KEAP1 (Kelch-like ECH-associated protein 1) and MPO (myeloperoxidase)). The peptide QPPALNDSYLYGPQ, with the lowest docking energy, was selected for a 100 ns molecular dynamics simulation. The results show that the peptide QPPALNDSYLYGPQ exhibited excellent stability when docked with KEAP1 and MPO, thus exerting antioxidant effects by regulating the KEAP1-NRF2 pathway and inhibiting MPO activity. This study further validates the antioxidant and self-assembling properties of the self-assembled supramolecules of Azumapecten farreri meat peptide and shows its potential for developing new, effective, and stable antioxidants.

Disulfide bond cleavage combined with critical pH induced unfolding and assembly of soy protein and its encapsulation effect on curcumin

The limited water solubility and bioactivity of hydrophobic phytochemicals can be improved and preserved by encapsulation technologies. In this research, a low-cost and low-energy encapsulation method was explored based on the self-assembly characteristics of soy protein (SP). The disulfide bond of SP was broken by Na2S2O5, and then the pH of SP was adjusted to the critical pH 10.5 with NaOH, which was the critical point of protein unfolding. The treated protein was added to curcumin (Cur), which was encapsulated in self-assembled protein nanoparticles during the subsequent neutralization process to obtain the soy protein-curcumin complex (SP-Cur). This process was known as the disulfide bond breaking combined with critical pH-driven technology. The cleavage of SP disulfide bonds was studied by the methods of 4, 4′-dithiopyridine (DPS) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). When the SP:Cur mass ratio was 1:1, the encapsulation efficiency (EE%) of Cur in SP-Cur obtained by disulfide bond breaking combined with the critical pH-driven method increased to 85.36 ± 1.03%. It was notably greater than the EE% of Cur in SP-Cur prepared by the pH-driven method (61.82 ± 1.54%) and the EE% of Cur in SP-Cur prepared by disulfide bond breaking treatment (66.38 ± 1.2%). The encapsulation of Cur in SP particles exhibited significant resistance to light and temperature, leading to enhanced stability. Soy protein treated with disulfide bond cleavage combined with critical pH-driven method can serve as a potential functional carrier to further incorporate hydrophobic compounds into food systems.

Constructing a hydrogel based on self-assembly properties of glycyrrhizic acid: A drug delivery system with digestive tract responsive

Glycyrrhizic acid (GA), an amphiphilic compound, is known for its natural sweetness and excellent self-assembly properties. Based on its self-assembled formulation forming ability, GA has been used as drug carriers and absorption enhancers, thereby altering the in vivo absorption kinetic processes of loaded drugs. This study mainly focuses on the influence of the GA self-assembled drug delivery system on the solubility, stability, and in vitro release of various active ingredients in traditional Chinese medicine, especially simulating the physiological rhythms and environment of in vivo absorption. Our findings indicate that GA has a significant solubilizing effect on poorly water-soluble components. The inclusion of GA improves the stability of the majority of the measured components to different extents in the digestive tract. Furthermore, in vitro release studies have demonstrated that the GA hydrogel system effectively slows drug release and is also enterosoluble, indicating responsiveness to the digestive tract, which contributes to stable concentrations of the drug in the blood. To sum up, the GA self-assembled drug delivery system can enhance solubility and stability to varying degrees by altering the in vivo absorption kinetics of representative active ingredients, exhibiting drug sustained release and self-assembly system enteric-like characteristics in different physiological environments. This indicates that the drug delivery system formed by GA through self-assembly can interact with the digestive tract environment, thus enhancing the in vivo bioavailability of drugs by influencing their biopharmaceutical properties.

Solar-enhanced lithium extraction with self-sustaining water recycling from salt-lake brines

Lithium is an emerging strategic resource for modern energy transformation toward electrification and decarbonization. However, current mainstream direct lithium extraction technology via adsorption suffers from sluggish kinetics and intensive water usage, especially in arid/semiarid and cold salt-lake regions (natural land brines). Herein, an efficient proof-of-concept integrated solar microevaporator system is developed to realize synergetic solar-enhanced lithium recovery and water footprint management from hypersaline salt-lake brines. The 98% solar energy harvesting efficiency of the solar microevaporator system, elevating its local temperature, greatly promotes the endothermic Li+ extraction process and solar steam generation. Benefiting from the photothermal effect, enhanced water flux, and enriched local Li+ supply in nanoconfined space, a double-enhanced Li+ recovery capacity was delivered (increase from 12.4 to 28.7 mg g-1) under one sun, and adsorption kinetics rate (saturated within 6 h) also reached twice of that at 280 K (salt-lake temperature). Additionally, the self-assembly rotation feature endows the microevaporator system with distinct self-cleaning desalination ability, achieving near 100% water recovery from hypersaline brines for further self-sufficient Li+ elution. Outdoor comprehensive solar-powered experiment verified the feasibility of basically stable lithium recovery ability (>8 mg g-1) directly from natural hypersaline salt-lake brines with self-sustaining water recycling for Li+ elution (440 m3 water recovery per ton Li2CO3). This work offers an integrated solution for sustainable lithium recovery with near zero water/carbon consumption toward carbon neutrality.

Living Self-Assembly of Monodisperse Micron-Sized Polymer Vesicles.

Artificial vesicles are recognized as powerful platforms for a large body of research across the disciplines of chemistry, physics and biology. Despite the great progress, control of the size distribution to make uniform vesicles remains fundamentally difficult due to the highly uncontrollable growth kinetics, especially for micron-sized vesicles. Here we report a template-free living self-assembly method to prepare monodisperse vesicles around 1 μm from an alternating copolymer. The polymer forms nanodisks (ca. 9 nm) in N,N-dimethylformamide (DMF), acting as seeds for subsequent growth. By adding water, the nanodisks gradually grow into larger circular bilayer nanosheets, which bend to crowns and continue to grow into uniform micron-sized vesicles. The first-order growth kinetics as well as the small size polydispersity index (<0.1) suggests the living self-assembly characteristics. This work paves a new way in both living self-assembly and monodisperse polymer vesicles.

Engineering Amino Acid and Peptide Supramolecular Architectures through Fluorination.

Fluorinated non-natural amino acids are attracting considerable research interest, especially in the biomedical field and in materials science, thanks to their ability to self-assemble into peculiar supramolecular structures. The conformational changes induced by the presence of fluorine atoms obviously affect their functions, as well as the biological activity of the deriving peptides and proteins. Here, we will briefly describe the main effects of fluorination on the aggregation behavior of such building blocks, focusing in particular on their improved tendency to form fibrils, and gels therefrom. Our aim is to underline the promising potential of fluorination as a tool to affect the self-assembly features of amino acids, both when used alone and when inserted into polypeptide sequences. The ability of fluorine to influence physical, chemical, and structural properties of these substrates offers the possibility to engineer bioinspired materials with specific and tunable functions.

HydrogelFinder: A Foundation Model for Efficient Self-Assembling Peptide Discovery Guided by Non-Peptidal Small Molecules.

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.

N-succinyl-chitosan as ecofriendly pesticide carriers: Nano encapsulation and synergistic antifungal effect on 4-hydroxyphenyl-2-propenyl-1-one derivatives based on chalcone structure

IntroductionTraditional pesticides have poor-water solubility, high toxicity and low bioavailability. Therefore, it is of great significance for the sustainable and healthy development of the pesticide industry to develop efficient and ecofriendly new chemical pesticide products and formulations. ObjectivesThis study aims to synthesize a series of derivatives based on chalcone structure (HPPO), and then use the amphiphilic and self-assembly characteristics of N-succinyl-chitosan (NSCS) to prepare HPPO@NSCS nanoparticles (HPPO@NSCS NPs) in order to realize the green application of HPPO, and investigate the antifungal activity and mechanisms of HPPO@NSCS NPs. MethodsNSCS was synthesized by structural modification using chitosan as the carrier. Based on its amphiphilic and self-assembly characteristics, HPPO-16@NSCS NPs were reasonably prepared by combining with active small molecule HPPO-16. Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), fluorescence spectroscopy (FS) and high-performance liquid chromatography (HPLC) were used to characterize the physicochemical properties of NSCS and HPPO-16@NSCS NPs. The inhibitory activity of nanopesticides against Rhizoctonia solani (R. solani) was tested in vivo and in vitro. The mechanism of antifungal action was discussed from the observation of pathogen morphology, fluorescence staining and enzyme activity determination. Results28 small molecules based on chalcone structure (HPPO-1-28), NSCS and HPPO-16@NSCS were successfully synthesized. The application of HPPO-16@NSCS could impair the development, cell structure, cellular energy utilization, and metabolism pathways of the fungi. The protective effects of HPPO-16@NSCS NPs on rice leaves and leaf sheaths were 80.9 and 76.1 %, respectively, which were better than those of azoxystrobin. ConclusionThis study reveals that these simple chalcone derivatives can be further explored as viable antibacterial alternatives and NSCS as a novel pesticide matrix can be used for the delivery of more insoluble pesticides.

Fibrillisation of faba bean protein isolate by thermosonication for process efficacy: Microstructural characteristics, assembly behaviour, and physicochemical properties

The effect of thermosonication (TS) (90 °C, 10–30 min) on the fibrillisation of faba bean protein isolate (FPI) was studied. The self-assembly behaviour, microstructural characteristics and techno-functional (gelation and emulsification) properties of FPI fibrils obtained from TS treatment were compared with those obtained from conventional prolonged heating (CH) at 90 °C up to 8 h. Compared to CH treatment, TS treatment was shown to significantly accelerate the formation of FPI fibrils with prominent β-sheet structures as revealed by Thioflavin T (ThT) fluorescence, Fourier-transform infrared spectroscopy (FTIR) and circular dichroism (CD). The characteristics of fibril building blocks were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography linked to tandem mass spectrometry (LC-MS/MS) to obtain the differences between TS and CH induced fibrillisation of FPI. Transmission electron microscopy (TEM) and small-angle neutron scattering (SANS) showed that 4 h CH and 10 min TS treatments resulted in the fibrils with similar radius (from 5 to 10 nm). Furthermore, SANS indicated that TS treatment induced the formation of an entangled FPI fibrillar network, which could lead to the observed viscoelastic properties of FPI at a high concentration (10 wt%). Finally, high internal phase O/W emulsions (HIPE, φ = 0.75) stabilised by 30 min TS induced FPI fibrils (3 wt%) demonstrated a stronger gel strength and smaller oil droplet size compared to those prepared with untreated FPI, suggesting a superior emulsification capability of FPI fibrils. This finding demonstrates that TS treatment is a promising and efficient method for fibrillisation of plant proteins with the resultant fibrils generating excellent gelation and emulsification properties.