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In this work, we developed a direct strategy to fabricate Palladene (i. e. Palladium metallene) aerogels and propose a temperature‐dependent growth mechanism. Besides the typical three‐dimensional networks and wrinkled surface morphologies, the as‐prepared Palladene50 ${{Palladene}_{50}}$ aerogel is endowed with abundant Pd2+. The as‐prepared Palladene50 ${{Palladene}_{50}}$ aerogel exhibits an excellent mass activity in the formic acid oxidation reaction and a good half‐wave potential in the oxygen reduction reaction in comparison with Pd/C and a Pd aerogel. This work expands the range of metal aerogels from the perspective of the building block units and demonstrates a direct approach to fabricate highly promising bifunctional electrocatalysts for fuel cells. [ABSTRACT FROM AUTHOR]

Tetraphenyl ethylene (TPE)-capped block copolypeptoid poly(N-butylglycine)-b-poly(N-ethylglycine) (TPE-PNBG-b-PNEG) was synthesized through the 1-(4-aminophenyl)-1,2,2-triphenylethene (TPE-NH2)-initiated ring opening polymerization of N-butylglycine N-thiocarboxyanhydride (NBG-NTA) and N-ethylglycine N-thiocarboxyanhydride (NEG-NTA). Three copolypeptoids with different mass ratios of hydrophilic PNEG block (wPNEG), TPE-PNBG10-b-PNEG41 (wPNEG = 70%), TPE-PNBG38-b-PNEG44 (wPNEG = 45%) and TPE-PNBG53-b-PNEG36 (wPNEG = 33%), were prepared by changing the feed molar ratios of monomer to initiator, whose compositions were confirmed by the proton nuclear magnetic resonance (¹H-NMR). Size exclusion chromatography (SEC) traces of the three copolypeptoids were all unimodal with narrow molecular mass distributions (Đ < 1.30). The ultraviolet-visible (UV-Vis) absorption spectra exhibited that TPE-PNBG-b-PNEG had a strong absorption at 316 nm, which was corresponding to the characteristic absorption of TPE group. TPE-PNBG-b-PNEG showed distinct aggregation-induced emission (AIE) property by adding water to its N,N-dimethylformamide (DMF) solution, which was caused by the assembly of hydrophobic TPE groups and PNBG segments in DMF-H2O system. When the initial water content (volume fraction) was 33%, TPE-PNBG53-b-PNEG36 assembled to spindle-like aggregates with an average length of 550 nm and width of 160 nm. When the initial water content was increased to 67%, TPE-PNBG53-b-PNEG36 assembled to worm-like aggregates with an average length of 650 nm and width of 90 nm. The higher initial water content would lead to the more tightly packed assemblies. With the increasing of wPNEG, TPE-PNBG38-b-PNEG44 assembled to pine leaf-like aggregates with an average length of 300 nm, while TPE-PNBG10-b-PNEG41 assembled to spherical micelles with a diameter around 50 nm. Under the excitation of 335 nm UV light, the assembly solution of the three copolypeptoids could emit strong blue light, with a maximum emission wavelength of 485 nm. The fluorescence intensity and fluorescence quantum yield of the assembly solution increased with the decreasing of wPNEG. As wPNEG gradually decreased, the packing parameters of TPE-PNBG-b-PNEG gradually increased, which led to the more compacted packing of the hydrophobic segments and subsequently enhanced the fluorescence intensity and fluorescence quantum yield due to the stronger AIE effect. [ABSTRACT FROM AUTHOR]

The self‐assembly of inorganic nanocrystals offers an efficient way for the fabrication of functional materials. However, it is still challenging for the construction of multidimensional nanostructures with controllable shapes, compositions and functions. Here, a series of heterostructures in different dimensions by surface modification of polyoxometalate (POM) clusters is developed. Three kinds of POM clusters (phosphomolybdic acid (PMA), phosphotungstic acid (PTA) and silicotungstic acid (STA) and five kinds of metal oxides (TiO2, VOx, La2O3, In2O3 and Gd2O3) can be used as building blocks, and a class of 1D, 2D and 3D heterostructures can be achieved by the control of surface ligand coverage. Compared with individual building blocks and other cluster‐based superstructures, TiO2‐PMA superstructures exhibit enhanced catalytic activity toward thioether oxidations, which is attributed to the electron transfer between TiO2 and POM clusters. [ABSTRACT FROM AUTHOR]

Transport and alignment of microscopic chips are important steps in microelectronics component integration with common approaches being pick‐and‐place, microfluidics, parallel transfer and self‐assembly. An alternate transport approach of microscopic chips is proposed using patterned liquid micro rails as chaperones. The surface free energy and interfacial free energy minimization of all constituents enable the creation of stable pathways. This allows for chip‐attachment to rails, while the liquid layer lubricates chip‐sliding. Monorails, digital monorails, and digital birails are investigated for chip movement behavior. Chip position and speed can be controlled using liquid flow in closed chambers. Speeds from 10 to 400 mm s−1 are achieved with translation distances as long as 50 mm. It is discovered that chips can selectively cross rail discontinuities of up to 500 µm, allowing for chip position control through a stop‐and‐go motion. A programmable liquid rails‐based chip conveyor system is demonstrated by transporting diodes to receptor sites where they undergo self‐assembly. [ABSTRACT FROM AUTHOR]

Diphenylalanine(FF)-Zn self-assembly (FS) confined in covalent organic polymers (FS@COPs) with efficient fluorescence was synthesized for fluorescence sensing of biogenic amines, which was one of the most important indicators for monitoring food freshness. FS@COPs combined excellent biodegradability of self-assembled dipeptide with chemical stability, porosity and targeted site recognition of COPs. With an optimal excitation wavelength of 360 nm and an optimal emission wavelength of 450 nm, FS@COPs could be used as fluorescence probes to rapidly visualize and highly sensitive determination of tryptamine (Try) within 15 min, and the linear range was from 40 to 900 μg L−1 with a detection limit of 63.08 μg kg−1. Importantly, the FS@COPs showed a high fluorescence quantum yield of 11.28%, and good stability, solubility, and selectivity, which could successfully achieve the rapid, accurate and highly sensitive identification of Try. Furthermore, we revealed the mechanism of FS@COPs for fluorescence sensing of targets. The FS@COPs system was applied to the fluorescence sensing of Try in real samples and showed satisfactory accuracy of 93.02%-105.25%. [ABSTRACT FROM AUTHOR]

Most chemotherapeutic agents are poorly soluble in water, have low selectivity, and cannot reach the tumor in the desired therapeutic concentration. On the other hand, sensitive hydrophilic therapeutics like nucleic acids and proteins suffer from poor bioavailability and cell internalization. To solve this problem, new types of controlled release systems based on nano-sized self-assemblies of cyclodextrins able to control the speed, timing, and location of therapeutic release are being developed. Cyclodextrins are macrocyclic oligosaccharides characterized by a high synthetic plasticity and potential for derivatization. Introduction of new hydrophobic and/or hydrophilic domains and/or formation of nano-assemblies with therapeutic load extends the use of CDs beyond the tried-and-tested CD-drug host–guest inclusion complexes. The recent advances in nano drug delivery have indicated the benefits of the hybrid amphiphilic CD nanosystems over individual CD and polymer components. This review provides a comprehensive overview of the most recent advances in the design of CDs self-assemblies and their use for delivery of a wide range of therapeutic molecules. It aims to offer a valuable insight into the many roles of CDs within this class of drug nanocarriers as well as current challenges and future perspectives. [ABSTRACT FROM AUTHOR]

Systems containing amphiphilic/pathic molecules have the tremendous capacity to self-assemble under appropriate conditions to form morphologies with well-defined structural order (systematic arrangement), nanometer-scale dimensions, and unique properties. In this work, the synthesis of novel naphthalimide-based amphiphilic probes that have 1,8-naphthalimide as the fluorescence signal reporting group, octyl as hydrophobic head, and PEG as hydrophilic tail, is described. These designed molecules represent a new class of self-assembling structures with some promising features. The lack of literature data on the use of 1,8-naphthalimides with cyclic and acyclic hydrophilic PEG fragments as self-assembling structures gives us the opportunity to initiate a new field in materials science. The successful synthesis of such structures is fundamental to synthetic chemistry, and computational studies of the aggregation and binding of water molecules shed light on the ability of these new systems to function as membrane water channels. This study not only expands the list of 1,8-naphthalimide derivatives but may also serve as a new platform for the development of membrane additives based on PEG-functionalized naphthalimides. [ABSTRACT FROM AUTHOR]

[Sn(H2PO4)2(TPyHP)](H2PO4)4∙6H2O (2), an ionic tin porphyrin complex, was synthesized from the reaction of [Sn(OH)2TPyP] (1) with a dilute aqueous solution of a polyprotic acid (H3PO4). Complex 2 was fully characterized using various spectroscopic methods, such as X-ray single-crystal crystallography, 1H NMR spectroscopy, elemental analysis, FTIR spectroscopy, UV–vis spectroscopy, emission spectroscopy, EIS mass spectrometry, PXRD, and TGA analysis. The crystal structure of 2 reveals that the intermolecular hydrogen bonds between the peripheral pyridinium groups and the axially coordinated dihydrogen phosphate ligands are the main driving force for the supramolecular assembly. Simultaneously, the overall association of these chains in 2 leads to an open framework with porous channels. The photocatalytic degradation efficiency of methyl orange dye and tetracycline antibiotic by 2 was 83% within 75 min (rate constant = 0.023 min−1) and 75% within 60 min (rate constant = 0.018 min−1), respectively. The self-assembly of 2 resulted in a nanostructure with a huge surface area, elevated thermodynamic stability, interesting surface morphology, and excellent catalytic photodegradation performance for water pollutants, making these porphyrin-based photocatalytic systems promising for wastewater treatment. [ABSTRACT FROM AUTHOR]

Magnetite nanoparticles (Fe3O4 NPs) have garnered significant attention over the past twenty years, primarily due to their superparamagnetic properties. These properties allow the NPs to respond to external magnetic fields, making them particularly useful in various technological applications. One of the most fascinating aspects of Fe3O4 NPs is their ability to self-assemble into complex structures. Research over this period has focused heavily on how these nanoparticles can be organized into a variety of superstructures, classified by their dimensionality—namely one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) configurations. Despite a wealth of studies, the literature lacks a systematic review that synthesizes these findings. This review aims to fill that gap by providing a thorough overview of the recent progress made in the fabrication and organization of Fe3O4 NP assemblies via a bottom-up self-assembly approach. This methodology enables the controlled construction of assemblies at the nanoscale, which can lead to distinctive functionalities compared to their individual counterparts. Furthermore, the review explores the diverse applications stemming from these nanoparticle assemblies, particularly emphasizing their contributions to important areas such as imaging, drug delivery, and the diagnosis and treatment of cancer. [ABSTRACT FROM AUTHOR]

The careful arrangement of nanomaterials (NMs) holds promise for revolutionizing various fields, from electronics and biosensing to medicine and optics. This review delves into the intricacies of nano-assembly (NA) techniques, focusing on oriented-assembly methodologies and stimuli-dependent approaches. The introduction provides a comprehensive overview of the significance and potential applications of NA, setting the stage for review. The oriented-assembly section elucidates methodologies for the precise alignment and organization of NMs, crucial for achieving desired functionalities. The subsequent section delves into stimuli-dependent techniques, categorizing them into chemical and physical stimuli-based approaches. Chemical stimuli-based self-assembly methods, including solvent, acid–base, biomolecule, metal ion, and gas-induced assembly, are discussed in detail by presenting examples. Additionally, physical stimuli such as light, magnetic fields, electric fields, and temperature are examined for their role in driving self-assembly processes. Looking ahead, the review outlines futuristic scopes and perspectives in NA, highlighting emerging trends and potential breakthroughs. Finally, concluding remarks summarize key findings and underscore the significance of NA in shaping future technologies. This comprehensive review serves as a valuable resource for researchers and practitioners, offering insights into the diverse methodologies and potential applications of NA in interdisciplinary research fields. [ABSTRACT FROM AUTHOR]

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers, in which the A blocks are negatively charged, and the B blocks are neutral. The electrostatic complexation between oppositely charged polymers drives the formation of many ordered phases. The microstructures and phase diagrams are calculated using self-consistent field theory (SCFT) based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged monomers. The effects of the charge ratio, representing the ratio of charges from the homopolymer over all charges from polymers in the system, on the ordered structure are systematically studied, both for hydrophobic and hydrophilic A blocks. The charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer concentration. We also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed, and the results are in good agreement with experiments. These studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems. [ABSTRACT FROM AUTHOR]

Hydrogels are widely used in various areas of human life. The vast majority of hydrogel materials used are polymer-based. Despite a number of advantages compared to polymer-based materials, studies on inorganic hydrogels are very limited and scattered. They are rarely offered as a basis for development of new functional materials. This review is an attempt to draw attention of researches to inorganic hydrogels. It describes currently existing methods for the synthesis of such hydrogels, their properties, and shows possible applications of the hydrogel materials. [ABSTRACT FROM AUTHOR]

In this paper we present a model containing modifications to the Signal-passing Tile Assembly Model (STAM), a tile-based self-assembly model whose tiles are capable of activating and deactivating glues based on the binding of other glues. These modifications consist of an extension to 3D, the ability of tiles to form "flexible" bonds that allow bound tiles to rotate relative to each other, and allowing tiles of multiple shapes within the same system. We call this new model the STAM*, and we present a series of constructions within it that are capable of self-replicating behavior. Namely, the input seed assemblies to our STAM* systems can encode either "genomes" specifying the instructions for building a target shape, or can be copies of the target shape with instructions built in. A universal tile set exists for any target shape (at scale factor 2), and from a genome assembly creates infinite copies of the genome as well as the target shape. An input target structure, on the other hand, can be "deconstructed" by the universal tile set to form a genome encoding it, which will then replicate and also initiate the growth of copies of assemblies of the target shape. Since the lengths of the genomes for these constructions are proportional to the number of points in the target shape, we also present a replicator which utilizes hierarchical self-assembly to greatly reduce the size of the genomes required. The main goals of this work are to examine minimal requirements of self-assembling systems capable of self-replicating behavior, with the aim of better understanding self-replication in nature as well as understanding the complexity of mimicking it. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrophilic cationic drugs such as mitoxantrone hydrochloride (MTO) pose a significant delivery challenge to the development of nanodrug systems. Herein, we report the use of a hydrophobic ion-pairing strategy to enhance the nano-assembly of MTO. We employed biocompatible sodium cholesteryl sulfate (SCS) as a modification module to form stable ion pairs with MTO, which balanced the intermolecular forces and facilitated nano-assembly. PEGylated MTO-SCS nanoassemblies (pMS NAs) were prepared via nanoprecipitation. We systematically evaluated the effect of the ratio of the drug module (MTO) to the modification module (SCS) on the nanoassemblies. The increased lipophilicity of MTO-SCS ion pair could significantly improve the encapsulation efficiency (∼97 %) and cellular uptake efficiency of MTO. The pMS NAs showed prolonged blood circulation, maintained the same level of tumor antiproliferative activity, and exhibited reduced toxicity compared with the free MTO solution. It is noteworthy that the stability, cellular uptake, cytotoxicity, and in vivo pharmacokinetic behavior of the pMS NAs increased in proportion to the molar ratio of SCS to MTO. This study presents a self-assembly strategy mediated by ion pairing to overcome the challenges commonly associated with the poor assembly ability of hydrophilic cationic drugs. [ABSTRACT FROM AUTHOR]

This article demonstrates the important roles of silicon in the nonclassical crystallization of goethite by particle attachment during limpet teeth formation and their structure–mechanical property relationship. [Display omitted] The intricate organization of goethite nanorods within a silica-rich matrix makes limpet teeth the strongest known natural material. However, the mineralization pathway of goethite in organisms under ambient conditions remains elusive. Here, by investigating the multi-level structure of limpet teeth at different growth stages, it is revealed that the growth of goethite crystals proceeds by the attachment of amorphous nanoparticles, a nonclassical crystallization pathway widely observed during the formation of calcium-based biominerals. Importantly, these nanoparticles contain a high amount of silica, which is gradually expelled during the growth of goethite. Moreover, in mature teeth of limpet, the content of silica correlates with the size of goethite crystals, where smaller goethite crystals are densely packed in the leading part with higher content of silica. Correspondingly, the leading part exhibits higher hardness and elastic modulus. Thus, this study not only reveals the nonclassical crystallization pathway of goethite nanorods in limpet teeth, but also highlights the critical roles of silica in controlling the hierarchical structure and the mechanical properties of limpet teeth, thus providing inspirations for fabricating biomimetic materials with excellent properties. [ABSTRACT FROM AUTHOR]

Efficient and durable non-precious cathode catalysts are needed at this hour for the development of fuel cells and metal-air batteries. The instability of one of the well-studied non-precious catalysts, Fe–N–C, in acidic electrolytes and its inferior bifunctional electrocatalytic activity in alkaline electrolytes, shifts the attention towards other electrocatalysts based on Ni and Co. Herein, we demonstrate the synthesis of nitrogen and transition metal (M=Co, Ni) co-doped mesoporous carbon (Co/Ni–N–mC) catalysts for bifunctional oxygen electrocatalysis. The synthetic approach involves the thermal annealing-induced transformation of the graphitic carbon nitride (g–C3N4) to nitrogen-doped graphitic mesoporous carbon (N–mC). The Co–N–mC catalyst has superior bifunctional oxygen electrocatalytic activity. It promotes the 4-electron pathway for the reduction of oxygen to water and is highly durable in alkaline electrolyte. The bifunctional activity is evaluated in terms of the potential gap (ΔE). The small ΔE for Co–N–mC makes it suitable for metal-air batteries. The rechargeable zinc-air battery is fabricated with Co–N–mC and it delivers a specific capacity of 718 mAh g−1Zn and a power density of 122.2 mW/cm2 with long-time charge-discharge cycling stability for 100 h. The synergistic effect between metal nanoparticles and nitrogen-doped carbon matrix, as well as the post-synthetic surface engineering-induced morphological changes, account for the enhanced activity. The transformation of supramolecular aggregate-derived metal-doped graphitic carbon nitride to electrocatalytically highly active nitrogen-doped mesoporous carbon and its electrocatalytic performance for aqueous rechargeable zinc-air battery is demonstrated. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonance (LSPR) in plasmonic nanomaterials can concentrate light in the nano‐dimension, leading to an enhancement of the light intensity by order of magnitude. While LSPR is a subject of extensive research in chalcogenide semiconductor nanocrystals (NCs), research on tellurium multinary chalcogenides (MnCs) remains elusive, possibly due to non‐availability of the corresponding quantum dots (QDs). In this report, we show the sequential switching of plasmonic to non‐plasmonic properties during the colloidal synthesis of AgInTe2 QDs. The reaction passes through several intermediates including AgInTe2/AgIn5Te8 core/shell NCs, AgInTe2 microrods (MRs), AgInTe2 QDs, and finally AgInTe2 quantum dot chain (QDC). Here, the AgInTe2/AgIn5Te8 core/shell NCs and AgInTe2 QDs depict strong LSPR absorption in the visible‐NIR region until ~2000 nm. We propose that small‐size quantum confined and cation deficient AgInTe2 particles are responsible for the observation of LSPR modes in both cases due to presence of the free carriers (holes). Our work on developing Te‐based plasmonic MnC QDs may find significant advancement in the nanoscale light‐matter interaction in semiconductor research. [ABSTRACT FROM AUTHOR]

In this study, a novel supramolecular composite, "photogels", was synthesized by mixing of cysteine–silver sol (CSS) and methylene blue (MB). A complex of modern physico-chemical methods of analysis such as viscosimetry, UV spectroscopy, dynamic and electrophoretic light scattering, scanning electron microscopy and energy-dispersive X-ray spectroscopy showed that MB molecules are uniformly localized mainly in the space between fibers of the gel-network formed by CSS particles. Molecules of the dye also bind with the surface of CSS particles by non-covalent interactions. This fact is reflected in the appearance of a synergistic anticancer effect of gels against human squamous cell carcinoma even in the absence of light irradiation. A mild toxic influence of hydrogels was observed in normal keratinocyte cells. Photodynamic exposure significantly increased gel activity, and there remained a synergistic effect. The study of free-radical oxidation in cells has shown that gels are not only capable of generating reactive oxygen species, but also have other targets of action. Flow cytometric analysis allowed us to find out that obtained hydrogels caused cell cycle arrest both without irradiation and with light exposure. The obtained gels are of considerable interest both from the point of view of academics and applied science, for example, in the photodynamic therapy of superficial neoplasms. [ABSTRACT FROM AUTHOR]

The separator is an essential component of sodium‐ion batteries (SIBs) to determine their electrochemical performances. However, the separator with high mechanical strength, good electrolyte wettability and excellent electrochemical performance remains an open challenge. Herein, a new separator consisting of amphoteric nanofibers with abundant functional groups was fabricated through supramolecular assembly of natural polymers for SIB. The uniform nanoporous structure, remarkable mechanical properties and abundant functional groups (e.g. −COOH, −NH2 and −OH) endow the separator with lower dissolution activation energy and higher ion migration numbers. These metrics enable the separator to lower the barrier for desolvation of Na+, accelerate the migration of Na+, and generate more stable solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). The battery assembled with the amphoteric nanofiber separator shows higher specific capacity and better stability than that assembled with glass fiber (GF) separator. [ABSTRACT FROM AUTHOR]

BACKGROUND: Hydroxyl radical‐mediated materials primarily liberate more reactive and acutely lethal hydroxyl radical (•OH) and act as potent bactericidal antibiotics, for example H2O2. Hydroxyl radical possess higher tendency than that of H2O2 to attack various biological molecules such as DNA, proteins and iron–sulfur clusters, and impair their proper functioning, actively leading to strongly potent bactericidal effect. To acquire the desired antimicrobial effect, high concentration of H2O2 is required that has found medically harmful to healthy tissues of humans. RESULTS: We herein report framework nucleic acid‐regulated DNAzyme cluster (FDC) – that is, peroxidase‐like hemin‐bound G‐quadruplex (G4/H) DNAzyme – to amplify the catalytic reduction potential of G4/H complex, leading to high conversion rate of H2O2 to more reactive hydroxyl radical that potentially shows the same antibacterial efficiency at lower and safer H2O2 concentration. Specifically, we have grafted multiple copies of DNAzymes outside framework nucleic acid (FNA) to successively achieve 3–9 orders of magnitude enhancement in catalytic activity and antibacterial efficiency of FDC. CONCLUSION: Our designed FDC has successfully alleviated H2O2 toxicity and increased its efficiency as antibacterial material, as FDC amplified the catalytic reduction potential of G4/H DNAzyme, leading to high conversion rate of H2O2 to more reactive •OH that potentially shows the same antibacterial efficiency at lower and safer H2O2 concentration. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Significant advancements have been achieved in polymer nanogel synthesis, yet there is a dearth of methods for easily preparing size‐adjustable, surface‐modifiable, and biocompatible nanogels. This study introduces a straightforward method for fabricating hyperbranched polyglycerol (HPG) nanogels in water through self‐assembly and disulfide bond crosslinking, avoiding the use of surfactants. The process involves modifying HPG with thioctic acid (TA) to create amphiphilic HPG‐TA rich in disulfide bonds, which is then reduced to facilitate water introduction and self‐assembly. Photocrosslinking is used to finalize the formation of HPG nanogels. These nanogels feature a uniform size distribution, with hydrodynamic diameters tunable from around 90 to 400 nm by tweaking synthesis variables. They have shown low cytotoxicity and high stability in aqueous media, with notable sensitivity to pH, especially in acidic conditions (e.g., pH 3), and redox‐responsiveness, as evidenced by reactions to 10 mM dithiothreitol (DTT). The nanogels' multiple hydroxyl groups enable easy functionalization, exemplified by the synthesis of fluorescent HPG‐RB nanogels. This work presents an efficient strategy for producing robust HPG nanogels, potentially spurring further advancements in the field of polymer nanogel synthesis and application. [ABSTRACT FROM AUTHOR]

Polyethyleneimine (PEI), a cationic hydrophilic polymer, and (phenylthio)acrylic acid (PTAA), a hydrophobic counter ion, were used to prepare ion pair self-assembly (IPSAM), which is sensitive to temperature and oxidation. The IPSAM was spontaneously formed when the amino group to carboxylic group molar ratio was 5/5 to 7/3. On the TEM micrograph, PEI/PTAA IPSAM was discovered as sphere-shaped nanoparticles with a diameter of tens of nanometers. The upper critical solution temperature (UCST) of the ion pair increased as the PTAA content increased and decreased when H2O2 oxidized the PTAA of the ion pair. The ion pair was interface active due to its amphiphilic property and the interface activity was decreased upon the PTAA oxidation. FT-IR and 1H NMR spectroscopy were used to verify the ionic interaction among PEI and PTAA, and X-ray photoelectron microscopy was used to confirm the oxidation of PTAA. The release of a payload (i.e. Nile red) in IPSAM was limited when the medium temperature was lower than the UCST but it was triggered above the phase transition temperature possibly due to the disintegration of the IPSAM. Upon oxidation, the UCST would decrease below the release medium temperature due to the PTAA oxidation causing promoted release and the release degree could occur readily in proportion to the H2O2 concentration. Schematic diagram of temperature and oxidation-responsive of PEI/PTAA self-assembly ion pairs (IPSAM) [ABSTRACT FROM AUTHOR]

Abstract Several bacterial strains have developed resistance against commercial antibiotics, and interestingly, supramolecular nanomaterials have shown considerable advantages for antibacterial applications. However, the main challenges in adopting nanotechnology for antibacterial studies are random aggregation, compromised toxicity, multi-step preparation approaches, and unclear structure-function properties. Herein, we designed the amphiphilic tripeptide that acts as a reducing and capping agent for silver metal to form silver-peptide colloidal nanohybrids with the mild assistance of UV light (254 nm) through the photochemical reduction method. The nanohybrids are characterized by different spectroscopic and microscopic techniques, and non-covalent molecular interactions between metal and peptide building blocks confirm their central role in the formation of nanohybrids. The tripeptide is biocompatible and can reduce the toxicity of silver ions (Ag+) by reducing to Ag0. These colloidal nanohybrids showed antibacterial activity against gram-negative and gram-positive bacterial strains, and the possible mechanism of killing bacterial cells could be membrane disruption. This synthetic strategy is facile and green, which helps avoid using toxic chemicals or reagents and complicated methods for colloidal nanohybrid preparation for biomedical applications.

The performance of a solid oxide fuel cell (SOFC) is strongly associated with the activity and durability of the cathode, where the oxygen reduction reaction occurs. In this study, we report our findings in the development of an Nb-doped PrBa0.8Ca0.2Co2O6−δ (PrBa0.8Ca0.2Co2−xNbxO6−δ, x = 0, 0.025, 0.05, and 0.1, denoted as PBCCNx) perovskite composite as the SOFC cathode. Analyses of X-ray diffraction (XRD) patterns and energy-dispersive transmission electron microscopy (TEM-EDS) images suggest that after being treated at 950 °C in air, PBCCN0.05 mainly contains phases of Ca- and Nb-doped PrBaCo2O6−δ double perovskite, PrCoO3 perovskite with Ca and Nb doping, and Ba3Ca1.18Nb1.82O9−δ. When evaluated as an SOFC cathode, the PBCCN0.05 mixture has shown a low polarization resistance of 0.0074 Ω∙cm2 at 800 °C in La0.8Sr0.2Ga0.8Mg0.2O3 electrolyte symmetrical cells. Accordingly, anode-supported single cells with a configuration of Ni–Zr0.84Y0.16O2−δ (YSZ)/YSZ/Gd0.1Ce0.9O2−δ/PBCCN0.05 display high electrochemical performance, with a peak power density of 1.81 W∙cm−2 and a reasonable durability of 100 h at 800 °C. PBCCN0.05 possesses a higher concentration of oxygen vacancies, a faster oxygen surface adsorption‒dissociation rate, and an increased mass ratio of PrCoO3 perovskite with Ca and Nb doping compared to PrBa0.8Ca0.2Co2O6−δ without Nb doping.

Abstract The wide-spreading of multidrug resistance poses a significant threat to human and animal health. Although antimicrobial peptides (AMPs) show great potential application, their instability has severely limited their clinical application. Here, self-assembled AMPs composed of multiple modules based on the principle of associating natural marine peptide N6 with ß-sheet-forming peptide were designed. It is noteworthy that one of the designed peptides, FFN could self-assemble into nanoparticles at 35.46 µM and achieve a dynamic transformation from nanoparticles to nanofibers in the presence of bacteria, resulting in a significant increase in stability in trypsin and tissues by 1.72–57.5 times compared to that of N6. Additionally, FFN exhibits a broad spectrum of antibacterial activity against multidrug-resistant (MDR) gram-positive (G+) and gram-negative (G−) bacteria with Minimum inhibitory concentrations (MICs) as low as 2 µM by membrane destruction and complemented by nanofiber capture. In vivo mouse mastitis infection model further confirmed the therapeutic potential and promising biosafety of the self-assembled peptide FFN, which can effectively alleviate mastitis caused by MDR Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and eliminate pathogenic bacteria. In conclusion, the design of peptide-based nanomaterials presents a novel approach for the delivery and clinical translation of AMPs, promoting their application in medicine and animal husbandry. Graphical Abstract

In this study, the mechanism of film formation through glutathione-induced lysozyme interface assembly was verified by spectroscopic methods, and the formed film was characterized by ellipsometry. N-(1-pyrenyl)maleimide (NPM) staining demonstrated that reduced glutathione broken the disulfide bonds of lysozyme leading to release of free sulfhydryl groups. Together, tryptophan fluorescence spectroscopy and lysozyme activity assay verified that the disulfide bond Cys6-Cys127 in lysozyme was broken. In addition, the unfolded lysozyme was found to still have antibacterial activity. The lysozyme film was transparent and colorless. Atom force microscopy (AFM) and transmission electron microscopy (TEM) revealed that it was composed of lysozyme aggregates with a uniform, smooth and dense surface. The results of X-ray photoelectron spectroscopy (XPS) and laser confocal Raman spectroscopy (LCRS) indicated that the lysozyme nanofilm might possess interfacial adhesion. The results of ellipsometry showed that the maximum thickness of the film was approximately 900 nm, and did not increase without limit with the increase in incubation time or the concentration of the reactants. Its stiffness value, elastic modulus and hardness were 29.32–34.21 μN/nm, 24.00–27.93 GPa, and 0.44–0.49 GPa, respectively, which were in the strength range of the protein film. The three-phase contact angle of the film was around 70°, indicating good hydrophilicity. Its thermal stability was high, and no degradation occurred at 200 ℃. The preparation of the lysozyme nanofilm provides a good idea and reference for the construction of novel edible coatings.

This study synthesized hawthorn polyphenol microparticles (HPM) based on the polyelectrolyte self-assembly technology. Plackett-burman combined with Box-Behnken design was used to study the factors affecting the preparation of HPM in response to the encapsulation efficiency and drug loading of hawthorn polyphenols. The Plackett-Burman design was used to screen for factors that significantly affect the outcomes, such as preparation time, sulfuric acid concentration, and the ratio of encapsulating materials, which were optimized through Box-Behnken response surface methodology. The morphology of HPM was examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and their gastrointestinal release kinetics were assessed using simulated gastric and intestinal fluids. The results indicated that the preparation time, sulfuric acid concentration, and the ratio of encapsulating materials significantly effect the fabrication of HPM. An encapsulation efficiency of 96.27%±1.37% was achieved with a preparation time of 3 h, a sulfuric acid concentration of 0.0254%, and a 4:1 ratio of chitosan to sodium alginate. Morphological analysis of HPM revealed irregularly shaped, well-dispersed spherical particles. The release rate of HPM in simulated intestinal fluid was higher than in gastric fluid, with the release kinetics corresponding to zero-order in gastric fluid and first-order in intestinal fluid. In summary, this study successfully produced HPM with a high encapsulation efficiency, substantial drug loading, and good dispersion. The HPM formulated could reduce the degradation of hawthorn polyphenols in the gastrointestinal tract, offering a novel approach for incorporating hawthorn polyphenols into food products.

Lithium-ion batteries (LIBs) are widely used as important energy storage and energy supply devices. The porous design and heteroatomization modification of carbon-based anode materials are crucial for achieving high-capacity and reversible energy storage in LIBs. Sol-gel method and pyrolysis treatment were used to obtain silica/silver composite particles used as templates. Polyphosphazene-coated silica/silver composite composite carbon materials (SiO2/Ag@PZS-C) were synthesized through in-situ self-assembly and carbonization of polyphosphazene. The electrochemical behavior and lithium storage mechanism of SiO2/Ag@PZS-C was also studied. The results reveal that the composite exhibited high specific capacity, stable cycling and superior rate performance. The double modification of silver nanoparticles and polyphosphazene carbon significantly improves the conductivity of silica and reduces the volume change. Moreover, the carbon shell of polyphosphazene facilitated the formation of a stable solid electrolyte interface film (SEI), preventing direct contact between the active material and the electrolyte, thereby substantially enhancing lithium storage performance.

Abstract The risk of ulcerative colitis (UC) is increasing worldwide with limited success using classical drugs, which has underscored the development of novel agents. Recently, carrier-free molecular assembly has been proven to be an effective drug delivery system, but it has yet to be examined for UC drug development using phytochemicals. Based on traditional Chinese medicine compatibility and potential medicinal uses, a pair of natural compounds, berberine (BBR) and magnolol (MAG), were found to self-assemble into nanostructures in aqueous solutions. Spectral analysis revealed that the assembly mechanisms of BBR and MAG were mediated through charge interactions and π-π stacking. Pharmacokinetic studies and animal imaging showed that BBR-MAG self-assembly (BM) effectively promoted the oral bioavailability and biodistribution of BBR in the colon. BM exhibited superior effects in regulating inflammatory factors, maintaining colon barrier integrity, and regulating gut microbiota in a dextran sulfate sodium salt-induced colitis mouse model. Additionally, no apparent signs of toxicity were observed, suggesting that BM has a favorable safety profile. This study presents a new strategy for UC management and highlights the cooperative effects of combined phytochemicals. Graphical Abstract

Three-dimensional (3D) stem cell models of the ovary have the potential to benefit womens reproductive health research. One such model, the reconstituted ovary (rOvary) self-assembles with pluripotent stem cell-derived germ cells creating a 3D ovarian mimic competent to support the differentiation of functional oocytes inside follicles. In this study, we evaluated the cellular composition of the rOvary revealing the capacity to generate multiple follicles surrounded by NR2F2+ stroma cells. However, the rOvary does not develop a surface epithelium, the source of second-wave pre-granulosa cells, or steroidogenic theca. Therefore, the rOvary models represent the self-assembly of activated follicles in a pre-pubertal ovary poised but not yet competent for hormone production.

The detoxification of lethal organophosphate (OP) residues in the environment is crucial to prevent human exposure and protect modern society. Despite serving as excellent catalysts for OP degradation, natural enzymes require costly preparation and readily deactivate upon exposure to environmental conditions. Herein, we designed and prepared a series of phosphotriesterase mimics based on stable, self-assembled peptoid membranes to overcome these limitations of the enzymes and effectively catalyze the hydrolysis of dimethyl p-nitrophenyl phosphate (DMNP)─a nerve agent simulant. By covalently attaching metal-binding ligands to peptoid N-termini, we attained enzyme mimetics in the form of surface-functionalized crystalline nanomembranes. These nanomembranes display a precisely controlled arrangement of coordinated metal ions, which resemble the active sites found in phosphotriesterases to promote DMNP hydrolysis. Moreover, using these highly programmable peptoid nanomembranes allows for tuning the local chemical environment of the coordinated metal ion to achieve enhanced hydrolysis activity. Among the crystalline membranes that are active for DMNP degradation, those assembled from peptoids containing bis-quinoline ligands with an adjacent phenyl side chain showed the highest hydrolytic activity with a 219-fold rate acceleration over the background, demonstrating the important role of the hydrophobic environment in proximity to the active sites. Furthermore, these membranes exhibited remarkable stability and were able to retain their catalytic activity after heating to 60 °C and after multiple uses. This work provides insights into the principal features to construct a new class of biomimetic materials with high catalytic efficiency, cost-effectiveness, and reusability applied in nerve agent detoxification.

We use a nonequilibrium variational principle to optimize the steady-state, shear-induced interconversion of self-assembled nanoclusters of DNA-coated colloids. Employing this principle within a stochastic optimization algorithm allows us to identify design strategies for functional materials. We find that far-from-equilibrium shear flow can significantly enhance the flux between specific colloidal states by decoupling trade-offs between stability and reactivity required by systems in equilibrium. For isolated nanoclusters, we find nonequilibrium strategies for amplifying transition rates by coupling a given reaction coordinate to the background shear flow. We also find that shear flow can be made to selectively break detailed balance and maximize probability currents by coupling orientational degrees of freedom to conformational transitions. For a microphase consisting of many nanoclusters, we study the flux of colloids hopping between clusters. We find that a shear flow can amplify the flux without a proportional compromise on the microphase structure. This approach provides a general means of uncovering design principles for nanoscale, autonomous, functional materials driven far from equilibrium.

The presented work proposes that the self-assembly of amphiphilic compounds in Xiaoqu Baijiu occurs at the distillation and condensation stage of Chinese Baijiu production for the first time. Such phenomena have similitude with the self-assembly nano-particles conducted by evaporation and condensation approaches. Hydrogen-bonding interactions prompting the formation of molecular clusters in the system. Herein, we characterized the variation of dipole moment, hydrogen bond strength, and cluster morphology in Xiaoqu Baijiu, based on electrochemical impedance spectroscopy, Raman spectroscopy, atomic force microscopy, and molecular dynamics simulation. The effects of major aroma substances on the self-assembly of Xiaoqu Baijiu were fully investigated, it turns out ethyl lactate had the strongest effect on resulting in self-assembled clusters.

[Display omitted] Acoustic levitation is a suitable approach for studying processes occurring at the gas–liquid interfaces, as it allows its investigation in a contact-free manner while providing control over the gas phase. Here, we hypothesize that phase transitions induced by a CO 2 rich atmosphere can be examined, at different length scales, in a contact-free manner. A system consisting of 12-hydroxysteric acid (HSA) soaps mixed with different ratios of monoethanolamine (MEA) and choline hydroxide, was prepared. Microliter droplets of the samples were acoustically levitated and monitored with a camera, while exposed to CO 2 to modify the pH through diffusion at the air–liquid interface and inside the droplet. The phase transition and water mobility in the levitated droplets were evaluated through X-ray scattering (SAXS/WAXS) and magnetic resonance studies, in real-time. Finally, the droplets were collected and examined under the microscope. The introduction of CO 2 gas induced a phase transition from micelles to multi-lamellar tubes, resulting in a gel-like behavior both in the bulk and at the interface. The high stability of the acoustic levitator allowed the investigation of this dynamic phenomenon, in real-time, in a contact-free environment. This study showcases the suitability of acoustic levitation as a tool to investigate complex chemical processes at interfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] Small molecule prodrugs self-assembled nano-delivery systems with tumor responsive linkages are emerging as an effective platform. However, the heterogeneity of tumor microenvironment may limit the anti-tumor effect of prodrug nanomedicines with a single response module. Here, we chose disulfide bond as the response module and branched chain alcohol as the self-assembly modification module to construct a single-responsive prodrug. We also constructed a double-responsive paclitaxel prodrug combining triglyceride and disulfide bond, taking into account of the highly expressed lipase and glutathione levels in tumor cells. The results showed that the anti-tumor effect of single-responsive branched chain alcohol modified prodrug nanoparticles was inferior to triglyceride prodrug nanoparticles with dual response modules. The triglyceride structure can not only serve as a self-assembly modification module, but also serve as a response module for intelligent drug release in tumor. Such dual roles will facilitate the efficient delivery of small molecule self-assembled prodrugs to tumor sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The peptide KIIF can self-assemble into bilayer nanotubes. • The introduction of acetonitrile had a great impact on the morphologies of KIIF self-assemblies. • Directional control over the shape and size of KIIF self-assemblies can be realized just by tuning acetonitrile content. • The role of acetonitrile in tuning morphologies of self-assemblies was revealed at microscopic level. The self-assembling morphologies of proteins, nucleic acids, and peptides are well correlated with their functioning in biological systems. In spite of extensive studies for the morphologies regulating, the directional control of the assembly morphology structure for the peptides still remains challenging. Here, the directional structure control of a bola-like peptide Ac-KIIF-CONH 2 (KIIF) was realized by introducing different amount of acetonitrile to the system. The morphologies were characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM), and the secondary structure was evaluated by circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that the introducing of different amount of acetonitrile has significantly tuned the hydrophobic interactions amongst the side chains, thus affecting the self-assembling morphologies. As acetonitrile content increased, the assemblies changed from nanotubes to helical/twisted ribbons and then to thin fibrils, with a steady decrease in the width. In contrast, the assemblies changed from thin fibrils to helical/twisted ribbons, and then to matured nanotubes, exhibiting a steady increase in the width with peptide concentration increasing. Complementary molecular dynamics (MD) simulations demonstrated the important role of acetonitrile in controlling the hydrophobic interactions, providing microscopic evidence for the structure transition process. We believe such observations provide important insights into the design and fabrication of functional materials with controlled shape and size. [ABSTRACT FROM AUTHOR]

Phospholipids are amphiphilic molecules able to adsorb at oil/water interfaces and thus used to stabilize parenteral emulsions. Yet, their low preferred curvature, which sensitively depends on molecular structures and interactions, favors the formation of lamellar phases and sets constraints on the system formulation. Combining phase studies, structural interfacial characterizations, and stability monitoring for different water/phospholipid/oil systems should shine a light on the mechanisms at play and thus tools to optimize formulations. Four phase diagrams were established for ternary aqueous systems containing either DOPC or POPC as the phospholipid and hexadecane or miglyol 812 as the oil. Droplet interfaces were probed using small-angle neutron scattering and the amount of adsorbed lipid was determined using separation and Raman spectroscopy. The metastability of both nano and macro emulsions was systematically assessed over weeks using light scattering. We show that nanoemulsion droplets are stabilized by a lipid monolayer and display excellent metastability if the preferred curvature is positive and large enough, even without any added charges or at high ionic strengths. In contrast, macroemulsion droplets are stabilized with a lipid multilayer, which should possess a positive preferred curvature but also a good enough interfacial anchorage, which is lost upon increasing the preferred curvature. Overall, we provide a rationale for understanding the impact of molecular changes in the formulation on emulsion metastability, through the analysis of the lipid film preferred curvature, layering, and interfacial anchorage.   [ABSTRACT FROM AUTHOR]

Nanocoating is a layer or coating on various drug delivery systems and medical devices within the nanometer range to improve the physicochemical properties, stability, compatibility and protect the materials from the external environment. The categories of materials used for the coating include polymers, metals, and carbon compounds. The technology is used for pharmaceutical as well as non-pharmaceutical areas. Nanocoating possesses some disadvantages and the need to use specialized instruments. Nanotechnology is beneficial from the developmental stages of the formulations to the finalized products and is one of the important methods to improve the efficiency of pharmaceutical products. [ABSTRACT FROM AUTHOR]

Through a large parameter space, electric fields can tune colloidal interactions and forces leading to diverse static and dynamical structures. So far, however, field-driven interactions have been limited to dipole-dipole and hydrodynamic contributions. Nonetheless, in this work, we propose that under the right conditions, electric fields can also induce interactions based on local chemical fields and diffusiophoretic flows. Herein, we present a strategy to generate and measure 3D chemical gradients under electric fields. In this approach, faradaic reactions at electrodes induce global pH gradients that drive long-range transport through electrodiffusiophoresis. Simultaneously, the electric field induces local pH gradients by driving the particle's double layer far from equilibrium. As a result, while global pH gradients lead to 2D focusing away from electrodes, local pH gradients induce aggregation in the third dimension. Evidence points to a mechanism of interaction based on diffusiophoresis. Interparticle interactions display a strong dependence on surface chemistry, zeta potential and diameter of particles. Furthermore, pH gradients can be readily tuned by adjusting the voltage and frequency of the electric field. For large Péclet numbers, we observed a collective chemotactic-like collapse of particles. Remarkably, such collapse occurs without reactions at a particle's surface. By mixing particles with different sizes, we also demonstrate, through experiments and Brownian dynamics simulations, the emergence of non-reciprocal interactions, where small particles are more drawn towards large ones.   [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: Self-driven actions, like motion, are fundamental characteristics of life. Today, intense research focuses on the kinetics of droplet motion. Quantifying macroscopic motion and exploring the underlying mechanisms are crucial in self-structuring and self-healing materials, advancements in soft robotics, innovations in self-cleaning environmental processes, and progress within the pharmaceutical industry. Usually, the driving forces inducing macroscopic motion act at the molecular scale, making their real-time and high-resolution investigation challenging. Label-free surface sensitive measurements with high lateral resolution could in situ measure both molecular-scale interactions and microscopic motion. Experiments: We employ surface-sensitive label-free sensors to investigate the kinetic changes in a self-assembled monolayer of the trimethyl(octadecyl)azanium chloride surfactant on a substrate surface during the self-propelled motion of nitrobenzene droplets. The adsorption–desorption of the surfactant at various concentrations, its removal due to the moving organic droplet, and rebuilding mechanisms at droplet-visited areas are all investigated with excellent time, spatial, and surface mass density resolution. Findings: We discovered concentration dependent velocity fluctuations, estimated the adsorbed amount of surfactant molecules, and revealed multilayer coverage at high concentrations. The desorption rate of surfactant (18.4 s−1) during the microscopic motion of oil droplets was determined by in situ differentiating between droplet visited and non-visited areas. [ABSTRACT FROM AUTHOR]

[Display omitted] Antimicrobial resistance (AMR) is a pressing global health concern. ESKAPEE pathogens, such as Methicillin-resistant Staphylococcus aureus (MRSA) are notable of concern in healthcare settings due to their resistance to critical antibiotics. To combat AMR, the development of alternatives such as bacterial membrane-active agents is crucial. Fatty acids (FAs) have emerged as a sustainable, antibiotic-free solution with inherent antibacterial activity. However, long chain saturated fatty acids (LCFAs) sodium soaps exhibit poorly antibacterial properties in comparison to short chain FAs, believed to be linked to limited solubility in aqueous media. We employed choline as a chaotropic organic counter-ion to enhance the solubility of LCFAs and investigated their antibacterial effects against MRSA. The optimal medium conditions for micelle formation for LCFAs was first investigated. Then, we determined the critical micelle concentration (CMC), micellar morphology, and aggregation number through surface tension measurements and small angle neutron scattering experiments. Antimicrobial activity was assessed using minimum bactericidal concentration (MBC) assays and time-kill experiments. We have identified conditions where LCFAs are effective against MRSA for the first time, providing valuable insights for developing new antibacterial agents to fight AMR. LCFAs need to be used above their Krafft temperatures and CMC to exhibit antibacterial efficacy. [ABSTRACT FROM AUTHOR]

Large macroscopic assemblies formed by a surfactant, sodium dodecylsulfate (SDS), and glycerol, can be directed to assemble in a hierarchical manner by the addition of a strong hydrogen-bond donor/acceptor, such as urea. Self-assembly in complex media is important to a range of applications, for instance in biological media, which are multi-component, to industrial formulations, where additives are present for flavour, texture, and preservation. Here, the gelation and self-assembly of sodium dodecylsulfate (SDS) in glycerol is explored in the presence of an additive, urea. Urea was chosen due to its importance both fundamentally and industrially, but also because of its ability to form strong H-bonds and interact with both glycerol and SDS. To cover the variety of length scales present in the gel-like phase, a combination of optical microscopy and small-angle X-ray scattering techniques were used to probe the micro- to nanoscale. On the microscale, the formation of a spectacular spherulite phase, even at low urea contents - 0.1 wt%, upon cooling was observed, a stark difference to the microfibrillar phase observed in the absence of urea. Interestingly, the nanostructure of the two crystalline phases were similar and showed negligible differences. This suggests that urea is not involved in the SDS/glycerol microfibril formation but instead directs the assembly of spherulites by bundling the microfibrils. These ternary systems are also probed as a function of urea content, SDS concentration, and temperature. The observations in this work highlight the importance of small molecules in the self-assembly process, which is relevant both fundamentally but also industrially, where small molecules are often added to formulations. [ABSTRACT FROM AUTHOR]

Polyamidoamine (PAMAM) dendrimer/phenylthio acetic acid (PTA) ion pair could be generated when the amino/carboxyl group ratio was 3/7 to 1/9. The chemical shifts on 1H NMR and FT-IR spectra suggested that PTA interacted ionically with PAMAM. The PTA was oxidized to sulfoxide and sulfone by H2O2, evidenced by 1H NMR and FT-IR spectroscopy. The ion pair exhibited upper critical solution temperature (UCST) and air/water interface-active which could decrease upon PTA oxidation. When the medium temperature was higher than the UCST, the substantial release of dye loaded in IPSAM took place in the H2O2 solution. [ABSTRACT FROM AUTHOR]

Low‐molecular‐weight (LMW) gelators are a versatile class of compounds able to self‐assemble and to form supramolecular materials, such as gels. The use of LMW peptides to produce these gels shows many advantages, because of their wide structure tunability, the low‐cost and effective synthesis, and the in vivo biocompatibility and biodegradability, which makes them optimal candidates for release and delivery applications. In addition, in these materials, the binding of the hosts may occur through a variety of noncovalent interactions, which are also the main factors responsible for the self‐assembly of the gelators, and through specific interactions with the fibers or the pores of the gel matrix. This review aims to report LMW gels based on amino acid and peptide derivatives used for the release of many different species (drugs, fragrances, dyes, proteins, and cells) with a focus on the possible strategies to incorporate the cargo in these materials, and to demonstrate how versatile these self‐assembled materials are in several applications. [ABSTRACT FROM AUTHOR]

Abstract Deoxyribonucleotide (DNA) is uniquely programmable and biocompatible, and exhibits unique appeal as a biomaterial as it can be precisely designed and programmed to construct arbitrary shapes. DNA hydrogels are polymer networks comprising cross-linked DNA strands. As DNA hydrogels present programmability, biocompatibility, and stimulus responsiveness, they are extensively explored in the field of biomedicine. In this study, we provide an overview of recent advancements in DNA hydrogel technology. We outline the different design philosophies and methods of DNA hydrogel preparation, discuss its special physicochemical characteristics, and highlight the various uses of DNA hydrogels in biomedical domains, such as drug delivery, biosensing, tissue engineering, and cell culture. Finally, we discuss the current difficulties facing DNA hydrogels and their potential future development. Graphical Abstract

Abstract The application of nanoscale scaffolds has become a promising strategy in vaccine design, with protein-based nanoparticles offering desirable avenues for the biocompatible and efficient delivery of antigens. Here, we presented a novel endogenous capsid-forming protein, activated-regulated cytoskeleton-associated protein (ARC), which could be engineered through the plug-and-play strategy (SpyCatcher3/SpyTag3) for multivalent display of antigens. Combined with the self-assembly capacity and flexible modularity of ARC, ARC-based vaccines elicited robust immune responses against Mpox or SARS-CoV-2, comparable to those induced by ferritin-based vaccines. Additionally, ARC-based nanoparticles functioned as immunostimulants, efficiently stimulating dendritic cells and facilitating germinal center responses. Even without adjuvants, ARC-based vaccines generated protective immune responses in a lethal challenge model. Hence, this study showed the feasibility of ARC as a novel protein-based nanocarrier for multivalent surface display of pathogenic antigens and demonstrated the potential of exploiting recombinant mammalian retrovirus-like protein as a delivery vehicle for bioactive molecules. Graphic Abstract

Dan Ye,1 Ding Ding,1 Ling-Yun Pan,2 Qing Zhao,3 Long Chen,2 Min Zheng,1 Tong Zhang,1 Bing-Liang Ma1 1Department of Pharmacology, School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, People’s Republic of China; 2Experiment Center for Science and Technology, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, People’s Republic of China; 3Department of Pharmacy, Jing’an District Zhabei Central Hospital, Shanghai, 200070, People’s Republic of ChinaCorrespondence: Bing-Liang Ma; Tong Zhang, Department of Pharmacology, School of Pharmacy, Shanghai University of Traditional Chinese Medicine, No. 1200 Cai Lun Road, Pudong New District, Shanghai, 201203, People’s Republic of China, Tel +86-021-5132 2199 ; +86-021-5132 2318, Fax +86-021-5132 2192, Email bingliang.ma@hotmail.com; zhangtongshutcm@hotmail.comPurpose: Docetaxel (DTX) is a valuable anti-tumor chemotherapy drug with limited oral bioavailability. This study aims to develop an effective oral delivery system for DTX using natural nanoparticles (Nnps) derived from Coptidis Rhizoma extract.Methods: DTX-loaded self-assembled nanoparticles (Nnps-DTX) were created using an optimized heat-induction strategy. Nnps-DTX’s shape, size, Zeta potential, and in vitro stability were all carefully examined. Additionally, the study investigated the encapsulation efficiency, loading capacity, crystal form, and intermolecular interactions of DTX in Nnps-DTX. Subsequently, the solubility, release, cellular uptake, metabolic stability, and preclinical pharmacokinetics of DTX in Nnps-DTX were systematically evaluated. Finally, the cytotoxicity of Nnps-DTX was assessed in three tumor cell lines.Results: Nnps-DTX was spherical in shape, 138.6 ± 8.2 nm in size, with a Zeta potential of − 20.8 ± 0.6 mV, a DTX encapsulation efficiency of 77.6 ± 8.5%, and a DTX loading capacity of 6.8 ± 1.9%. Hydrogen bonds, hydrophobic interactions, and electrostatic interactions were involved in the formation of Nnps-DTX. DTX within Nnps-DTX was in an amorphous form, resulting in enhanced solubility (23.3 times) and release compared to free DTX. Following oral treatment, the mice in the Nnps-DTX group had DTX peak concentrations 8.8, 23.4, 44.6, and 5.7 times higher in their portal vein, systemic circulation, liver, and lungs than the mice in the DTX group. Experiments performed in Caco-2 cells demonstrated a significant increase in DTX uptake by Nnps-DTX compared to free DTX, which was significantly inhibited by indomethacin, an inhibitor of caveolae-mediated endocytosis. Furthermore, compared to DTX, DTX in Nnps-DTX demonstrated better metabolic stability in liver microsomes. Notably, Nnps-DTX significantly reduced the viability of MCF-7, HCT116, and HepG2 cells.Conclusion: The novel self-assembled nanoparticles considerably enhanced the cellular absorption, solubility, release, metabolic stability, and pharmacokinetics of oral DTX and demonstrated strong cytotoxicity against tumor cell lines. Keywords: docetaxel, oral delivery, self-assembly, nanoparticles, pharmacokinetics, coptidis rhizoma

Constructing an edible extracellular matrix (ECM) scaffold with good thermal stability, self-assembly properties and biocompatibility is crucial for manufacturing structured cell cultured meat products. In this study, carboxymethyl chitosan (CMCS) was introduced into the bovine bone collagen (BBC) system. Using ultraviolet (UV) absorption, infrared (IR) and fluorescence spectroscopy, it was found that the interaction between BBC and CMCS was enhanced with the increase in CMCS concentration, without affecting the triple-helical structure. The results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that the introduction of CMCS reinforced the thermal stability of BBC. Turbidity test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed an increase in the degree of fibrillogenesis and aggregation behavior and changes in self-assembly rate; a looser and twisted three-dimensional structure with a larger fibril diameter and a wider diameter distribution was observed after the introduction of CMCS. However, the introduction of CMCS did not significantly affect the formation and length of D-periodicity (a characteristic alternating light/dark transverse stripe structure formed during the self-assembly process of collagen fibers) in BBC, and there was no significant difference in the cell compatibility of the system before and after the introduction of CMCS. The BBC-CMCS interaction might be dominated more by electrostatic forces than covalent interactions and hydrogen bonds with the increase in CMCS concentration. These results indicated that the introduction of CMCS improved the thermal stability and self-assembly properties of BBC without affecting its biocompatibility or triple-helical integrity. This study provides a reference for the development of excellent edible collagen-based ECM as a biomimetic scaffold for cultured meat and for the deep processing and high-value utilization of livestock and poultry bone by-products.

Oligopeptides stand out for their remarkable structural variability, ease of synthesis, and amenability to functionalization, making them exceedingly appealing for crafting functional nanostructured materials. The low metabolic stability of natural peptides can be overcome by replacing α-amino acids with β3- amino acids, to yield artificial peptides best described as substituted β3-oligoamides. Controlling the morphology of such structures by varying the amino acid residues and altering the oligoamide termini makes it possible to adapt the core design to a range of hierarchical structures and function. Conductivity is a desired property in such nanomaterials; preferably conductive materials should be chemically anchored to a highly conductive metal, such as gold surface to connect to macroscopic electronics. It is preferable to use thiol functionality, however β3 cysteine is not synthetically achieveable. In this study β3 [SLIA] oligoamide has been synthesized and functionalized at the N terminus with a thiol moiety. After successful synthesis and purification, the thiolated oligoamide was physically characterized to confirm binding to gold, self-assembly and hetero assembly on these anchor points. It was demonstrated with a quartz crystal microbalance (QCM) that self-assembling monolayers can be formed on a gold surface and the formation of a S-Au bond was confirmed with X-ray photoelectron spectroscopy. Growth of Ac-β3[WKLWEL] fibres on these anchor points was confirmed by using atomic force microscopy and QCM. Hence, a viable metal anchor has been established that lays the foundations for the future development of molecular electronics based on β3 oligoamides.

Abstract Background Frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-TDP), amyotrophic lateral sclerosis (ALS) and limbic-predominant age-related TDP-43 encephalopathy (LATE) are associated with deposition of cytoplasmic inclusions of TAR DNA-binding protein 43 (TDP-43) in neurons. One complexity of this process lies in the ability of TDP-43 to form liquid-phase membraneless organelles in cells. Previous work has shown that the recombinant, purified, prion-like domain (PrLD) forms liquid droplets in vitro, but the behaviour of the complementary fragment is uncertain. Methods We have purified such a construct without the PrLD (PrLD-less TDP-43) and have induced its phase separation using a solution-jump method and an array of biophysical techniques to study the morphology, state of matter and structure of the TDP-43 assemblies. Results The fluorescent TMR-labelled protein construct, imaged using confocal fluorescence, formed rapidly (