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Supramolecular peptide assemblies have been widely used for the development of biomedical, catalytical, and optical materials with chiral nanostructures in view of the intrinsic chirality of peptides. However, the assembly pathway and chiral transformation behavior of various peptides remain largely elusive especially for the transient assemblies under out‐of‐equilibrium conditions. Herein, the N‐fluorenylmethoxycarbonyl‐protected phenylalanine‐tyrosine dipeptide (Fmoc‐FY) was used as a peptide assembly platform, which showed that the assembly proceeds multistep evolution. The original spheres caused by liquid‐liquid phase separation (LLPS) can nucleate and elongate into the formation of right‐handed helices which were metastable and easily converted into microribbons. Interestingly, a bipyridine derivative can be introduced to effectively control the assembly pathway and induce the formation of thermodynamically stable right‐handed or left‐handed helices at different stoichiometric ratios. In addition, the chiral assembly can also be regulated by ultrasound or enzyme catalysis. This minimalistic system not only broadens the nucleation‐elongation mechanisms of protein aggregates but also promotes the controllable design and development of chiral biomaterials. [ABSTRACT FROM AUTHOR]

Variable (wavelength) selection is essential in the multivariate analysis of near-infrared spectra to improve model performance and provide a more straightforward interpretation. This paper proposed a new variable selection method named binning-normalized mutual information (B-NMI) based on information entropy theory. "Data binning" was applied to reduce the effects of minor measurement errors and increase the features of near-infrared spectra. "Normalized mutual information" was employed to calculate the correlation between each wavelength and the reference values. The performance of B-NMI was evaluated by two experimental datasets (ideal ternary solvent mixture dataset, fluidized bed granulation dataset) and two public datasets (gasoline octane dataset, corn protein dataset). Compared with classic methods of backward and interval PLS (BIPLS), variable importance projection (VIP), correlation coefficient (CC), uninformative variables elimination (UVE), and competitive adaptive reweighted sampling (CARS), B-NMI not only selected the most featured wavelengths from the spectra of complex real-world samples but also improved the stability and robustness of variable selection results. [ABSTRACT FROM AUTHOR]

[Display omitted] Development of peptide-based supramolecular materials with hierarchical morphology and tunable guest loading displays broad potential as drug carrier in view of biocompatibility and biodegradability. Herein, we report a facile Schiff base nanoarchitectonic for supramolecular assembly of diphenylalanine (FF) metastable gel. The addition of trace glutaraldehyde (GA)/H 2 O solution induces the Schiff base reaction between GA and FF accompanying by phase transition from gel to solution. FF nanoparticles and hierarchical beaded nanofibers with autofluorescence properties can be constructed by regulating the competitive assembly between FF-H 2 O and FF-GA oligomer. Moreover, various guest molecules with different hydrophilic and hydrophobic properties can be easily loaded into such assembled particles and its release can be triggered under weak alkaline conditions, which show the potential application of the assembled FF system as drug carriers. [ABSTRACT FROM AUTHOR]

Control of symmetry breaking of materials provides large opportunities to regulate their properties and functions. Herein, we report breaking the symmetry of layered dipeptide crystals by utilizing CO2 to induce the adjacent monomolecular layers to stack from the opposite to the same direction. The role of CO2 is to cover the interlayer interaction sites and force the dipeptides to adsorb at asymmetric positions. Further, the dipeptide crystals exhibit far superior piezoelectricity after symmetry breaking and the piezoelectric voltage generated from the dipeptide‐based generators becomes more than 500 % higher than before. This work reveals a potential route to engineer structures and properties of layered materials and provides a deep insight into the control of non‐covalent interactions. [ABSTRACT FROM AUTHOR]

Multicolor luminescent segmented materials have attracted tremendous research interest due to their potential applications as barcoding materials in information security and anti‐counterfeiting. Although much effort has been devoted to the preparation of photonic barcodes based on different light‐emitting materials, the rational design of barcoding materials with well‐controlled emission color and length at desired position remains a challenge. Here, a novel strategy to fabricate multicolor luminescent segmented 1D molecular crystals is reported by manipulating the molecular conformation and intermolecular interactions of the mechanochromic crystals, which are assembled from a rationally designed twisting conjugated molecule. The emission color of these mechanochromic crystals changes from green to orange with the mechanism of synergy effect of force‐induced molecular isomerization from trans to cis state and molecular packing changes from cross to parallel, which is revealed by single crystal X‐ray diffraction. Multicolor luminescent segmented 1D microribbons are fabricated by applying precisely controlled forces by tapping mode atomic force microscope, which shows the encoding capability. These findings provide a new method that allows the controllable fabrication of segmented materials with tunable emission color and length at desired position toward barcoding applications. [ABSTRACT FROM AUTHOR]

It is commonly considered that amyloid‐β (Aβ) fibrils are heavily involved in the neurological diseases. Establishing an external model based on the core recognition motif (diphenylalanine, FF) of Aβ would be of significance in understanding the assembly and disassembly of Aβ fibrils in living system. Herein, supramolecular gels with structure transition from amyloid‐like β‐sheet to different supramolecular helices were obtained through the co‐assembly of a N‐fluorenylmethoxycarbonyl‐protected L‐FF (L‐FmocFF) with achiral pyridine derivatives. It is found that the different stacking modes (H‐ or J‐aggregates) of additives and the microenvironment of chiral carbon play vital roles for the selectively chiral transfer or amplification of L‐FmocFF. The dynamic process of helix formation was also captured. This work provides a convenient co‐assembly way to explore the structure basis of Aβ fibrils with a controlled chirality. [ABSTRACT FROM AUTHOR]

Single-tailed and gemini-type supra-gelators were facilely fabricated via the conjugation of the D - or L -enantiomeric dihydrazide TDH with single-tailed achiral aldehyde C12BAD through dynamic acylhydrazone bonding. Chirality transfer from small molecules to supramolecules was successfully achieved via the spontaneous assembly of the formed supra-gelators into supramolecular chiral hydrogels. [ABSTRACT FROM AUTHOR]

Zwitterionic amphiphiles with covalently bonded anionic and cationic groups exhibit electrically neutral properties but extremely high polarity. Under most circumstances, their charge densities can be simply and reversibly modulated by pH values. Such unique structures and properties distinguish them from all other types of amphiphiles. In this review, we summarize the assembly characteristics of zwitterionic amphiphiles and put forward our important fundamental opinions on how to design and modify zwitterionic amphiphiles to achieve abundant aggregate structures and multifunctions. More importantly, this kind of amphiphile shows mildness, better wettability, good biocompatibility, biostability, nonfouling and functionalizable properties, as well as an excellent synergistic effect with other amphiphiles, which makes them promising candidates for applications in household cleaning, cosmetics, electrochemistry, intelligent soft materials and biology. Based on the matchless advantages of zwitterions, we focus on the introduction of zwitterionic betaine and imidazolium amphiphiles and explore their applications in target ion conduction, noble metal nanomaterials and antifouling biomaterial preparation. As far as we know, there has been no review of the aggregation behavior and green applications of zwitterionic amphiphiles so far. We expect to provide readers with a comprehensive overview of their assembly strategies, practical methodologies and future potential progression, as well as to promote greater interest and further developments in this field. [ABSTRACT FROM AUTHOR]

Ultra-fast self-healing organogels based on dynamic covalent chemistry for dye adsorption were prepared from polyvinyl alcohol (PVA), 4-formylphenylboronic acid (FPBA), and tartaric acid dihydrazide (TDH) by an effective in situ reaction approach. The relative xerogels can adsorb methylene blue selectively with high efficiency. The boronate ester bonds and acylhydrazone bonds endow organogels with a very fast self-healing property. What's more, the chirality can be transferred from TDH to the organogels. The organogels obtained from l-TDH and d-TDH show opposite chirality according to the circular dichroism spectra. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) have attracted much attention in the field of photochromic materials. However, POM‐based photochromic supramolecular hydrogels with high transparency and good photochromic properties are seldom reported. In this work, a homogenous, optically transparent, injectable, and photochromic supramolecular hydrogel was fabricated through the coassembly of ammonium heptamolybdate (Mo7) and an imidazolium‐based zwitterionic amphiphile (3‐(1‐hexadecyl‐3‐imidazolio)propanesulfonate (C16IPS)). The balance between electrostatic attraction and repulsion of Mo7 clusters and zwitterionic amphiphiles enables them to coassemble into a homogenous and transparent supramolecular hydrogel. By adjusting the molar ratio of C16IPS/Mo7, ordered spherical micelle‐based hydrogels and aligned wormlike micelle‐based hydrogels can be obtained. The incorporation of Mo7 into hydrogels endows these hydrogels with excellent photochromic properties. Specifically, after coassembly with C16IPS, the photochromic ability of hydrogels is significantly enhanced compared with that of a pure aqueous solution of Mo7. These hydrogels exhibit great potential applications as photochromic materials for the recording of rewritable information. [ABSTRACT FROM AUTHOR]

The co‐existence of electrostatic attraction and repulsion between zwitterionic amphiphile and anionic polyoxometalate (POM) promotes the formation of aqueous inorganic–organic coassemblies. Injectable, luminescent supramolecular hydrogels have been fabricated by using this novel and versatile technique. Hydrogels with different characteristics can be flexibly manipulated by adjusting the molar ratios of compounds. Interestingly, a linear relationship between the luminescence intensity and temperature accompanying the sol‐gel transition was observed. In addition, the emission properties of the hydrogels were sensitive to external acid and base gasses. Such multi‐stimuli responsive luminescent hydrogels provide an attractive pathway to construct intelligent optical soft materials, especially for biological sensors for which stimuli responsiveness is necessary. Let it gel: Injectable, luminescent hydrogels were fabricated by inorganic–organic coassembly. Reversible sol‐gel transitions could be achieved by thermal treatment, which were accompanied by a change of fluorescence intensity. The photoluminescence of the samples was quenched with HCl gas and recovered with NH3 gas. [ABSTRACT FROM AUTHOR]

Abstract: A low‐molecular‐weight supramolecular hydrogel has been fabricated based on host–guest interactions between β‐cyclodextrin (β‐CD) and an asymmetric gemini zwitterionic liquid (ZIL) containing an azobenzene and bis(trifluoromethanesulfonyl)imide. Reversible sol–gel phase transitions were triggered by light and temperature. The binding stoichiometry, mainly noncovalent interactions in the hydrogel, photo‐ and thermoresponsive mechanisms, and mode of inclusion in the complex were studied in detail by NMR spectroscopy, UV/Vis spectroscopy, isothermal titration calorimetry, and control experiments. Interestingly, the β‐CD in the complex can be photo‐manipulated to shuttle along the guest molecule, accompanied by a change in the circular dichroism signals. Reversible switching of the conductivity accompanies the sol–gel phase transition, which demonstrates the stability of the supramolecular hydrogel and its potential application in multi‐stimuli‐responsive electric sensor materials. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, we propose a novel strategy for preparing supramolecular self‐assemblies for pH‐responsive drug delivery. In alkaline solutions, a novel supra‐amphiphile can be fabricated by a cationic surfactant dodecyl[2‐(4‐formylphenoxy)ethyl] dimethylammonium bromide (C12‐CHO) and a drug molecule (isonicotinic acid hydrazide) via a dynamic covalent bond. The constructed supra‐amphiphile can hierarchically self‐assemble into ordered micelles, which facilitates its use for drug delivery. Interestingly, the supra‐amphiphile can facilely disassemble under specific acidic conditions, which is convenient for controlled release of drugs. Thus, this ionic amphiphile‐drug system paves a way for realizing pH‐driven targeted drug release. [ABSTRACT FROM AUTHOR]

Abstract: Gelation mechanism is of utmost importance to the rational design of supramolecular hydrogelators. Although both kinetic and thermodynamic controlled self‐assembly processes have been widely studied in hydrogels, the formation relationship between crystalline and amorphous gel networks still remains ambiguous. Herein, a gelation transformation from a kinetic to a thermodynamic process was achieved by balancing the rigidity and flexibility of the inorganic–organic co‐assemblies. By using polyoxometalates and zwitterionic amphiphiles, the transition morphologies between crystalline and amorphous hydrogel networks were evidenced for the first time, as ordered wormlike micelles. Given the versatile applications of hydrogels in biological systems and materials science, these findings may highlight the potential of inorganic–organic binary supramolecular hydrogelators and fill in the blank between kinetic and thermodynamic controlled gelation processes. [ABSTRACT FROM AUTHOR]

The relaxation behaviors of thin polymer films show a strong dependence on temperature and film thickness. Direct quantitative detection of the relaxation behaviors of thin polymer films at nanometer scale by traditional instruments is however challenging. In this study, we employed atomic force microscopy (AFM)-based force-distance curve to study the relaxation dynamics and the film thickness dependence of glass transition temperature ( T) for normal thin polystyrene (PS) films supported on silicon substrate. The adhesion force ( F) between AFM tip and normal thin PS film surfaces was quantitatively detected in situ under the variation of temperature and film thickness. The T of normal thin PS film was successfully obtained by the abrupt variation of F under temperature stimulation. Our result showed that the T of normal thin PS films decreased with the decreasing film thickness. The study here could be beneficial for understanding the relaxation dynamics of normal thin polymer films. [ABSTRACT FROM AUTHOR]

In this study, we present a facile method to construct highly ordered and well-defined ionic channels in anion-exchange membranes (AEMs) through in-phase photopolymerization of liquid crystals (LCs). Hexagonal and lamellar LC samples were prepared by the self-organization of polymerizable amphiphilic imidazolium-based ionic liquids. The preservation of LC nanostructures in the obtained polymeric membranes was confirmed by the combination of small-angle X-ray scattering (SAXS), polarized optical microscope (POM), and scanning electronic microscopy (SEM) measurements. Phase separations of LCs at the molecular level provided highly ordered and well-defined ionic channels for efficient anion conduction and meanwhile maintained a strong hydrophobic domain to suppress the swelling degree. The membranes synthesized in the present work provide a promising model system for understanding the idea of constructing ionic highways in AEMs through self-organization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first time using CBAM-CNN to predict particle size distribution during fluidized bed granulation. • The CBAM-CNN model was optimized by introducing Bayesian optimization and C-Mixup algorithms. • The performance of CBAM-CNN was compared to other classic models. • The modeling convenience of CBAM-CNN was evaluated. Monitoring the particle size distribution (PSD) is crucial for controlling product quality during fluidized bed granulation. This paper proposed a rapid analytical method that quantifies the D10, D50, and D90 values using a Convolutional Block Attention Module-Convolutional Neural Network (CBAM-CNN) framework tailored for deep learning with near-infrared (NIR) spectroscopy. This innovative framework, which fuses CBAM with CNN, excels at extracting intricate features while prioritizing crucial ones, thereby facilitating the creation of a robust multi-output regression model. To expand the training dataset, we incorporated the C-Mixup algorithm, ensuring that the deep learning model was trained comprehensively. Additionally, the Bayesian optimization algorithm was introduced to optimize the hyperparameters, improving the prediction performance of the deep learning model. Compared with the commonly used Partial Least Squares (PLS), Support Vector Machine (SVM), and Artificial Neural Network (ANN) models, the CBAM-CNN model yielded higher prediction accuracy. Furthermore, the CBAM-CNN model avoided spectral preprocessing, preserved the spectral information to the maximum extent, and returned multiple predicted values at one time without degrading the prediction accuracy. Therefore, the CBAM-CNN model showed better prediction performance and modeling convenience for analyzing PSD values in fluidized bed granulation. [ABSTRACT FROM AUTHOR]

The exploration of short peptide-based assembly is vital for understanding protein-misfolding-associated diseases and seeking strategies to attenuate aggregate formation. While, the molecular mechanism of their structural evolution remains poorly studied in view of the dynamic and unpredictable assembly process. Herein, infrared (IR) spectroscopy, which serves as an in situ and real-time analytical technique, was intelligently employed to investigate the mechanism of phase transition and aggregate formation during the dynamic assembly process of diphenylalanine. Combined with other spectroscopy and electron microscopy technologies, three stages of gel formation and the main driving forces in different stages were revealed. A variety of stoichiometric methods such as continuous wavelet transform, principal component analysis, and two-dimensional correlation spectroscopy techniques were conducted to analyze the original time-dependent IR spectra to obtain detailed information on the changes in the amide bands and hydration layer. The microenvironment of hydrogen bonding among amide bands was significantly changed with the addition of pyridine derivatives, resulting in great differences in the properties of co-assembled gels. This work not only provides a universal analytical way to reveal the dynamic assembly process of dipeptide-based supramolecular gel but also expands their applications in supramolecular regulation and high-throughput screens in situ.

The co-assembly of zwitterionic amphiphile and polyoxometalate is a new and promising technique to construct a hierarchical and multifunctional supramolecular hydrogel. To comprehensively investigate the assemble mechanism, zwitterionic amphiphiles with different cations, namely, 3-(1-hexadecyl-3-imidazolio) propanesulfonate (C 16 IPS) and 3-(1-hexadecyl-2-methyl-3-imidazolio) propanesulfonate (C 16 bIPS), were designed to complex with silicotungstic acid (HSiW). Hydrogen bonding between the oxygen atoms of HSiW and the protons on C-2 of the imidazolium rings and the steric effect significantly influence the morphology and rheological property of the hydrogel. Interestingly, cross-linked worm-like micelles in parallel, vertical, and tilted distribution were observed using cryogenic transmission electron microscopy. In addition, these aggregates were further stacked into hexagonal phases on a large scale. Hence, deep insights into the relationship among the structure of zwitterionic amphiphile, self-assembled architecture, and the mechanical property of a polyoxometalate-based hydrogel were disclosed.

Supramolecular thermotropic ionic liquid crystals (ILCs) with hexagonal and lamellar phases were fabricated by the self-assembly of zwitterionic ionic liquids, which were formed by 3-(1-alkyl-3-imidazolio) propanesulfonate with different alkyl chain lengths C n IPS ( n = 12, 14, 16) and 3,4,5-tris(dodecyloxy)benzoic acid (TDBA) based on intermolecular electrostatic interactions. The phase behaviors of ILCs were investigated by differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), and polarized optical microscopy (POM). The highly ordered and well-defined microstructure of ILCs can be considered to be proton pathways and to radically improve the ionic conductivity, suggesting the induction of proton conduction through a hopping mechanism.

We herein report a smart amphiphilic supramolecular complex ([MimA-EDA-MimA]@[DBS] 2 ) with stimuli-responsive self-assembly, constructed by 3-(3-formyl-4-hydroxybenzyl)-1-methylimidazolium chloride (MimACl), sodium dodecyl benzene sulfonate (SDBS), and ethylenediamine (EDA). The self-assembly of [MimA-EDA-MimA]@[DBS] 2 shows triple-sensitivities in response to pH, concentration, and salt. At a low pH, only micelles are formed, which can transform into vesicles spontaneously when the pH increases to 11.8. Vesicles can gradually fuse into vesicle clusters and elongated assemblies with increasing concentration of [MimA-EDA-MimA]@[DBS] 2 . Chainlike aggregates, ringlike aggregates, or giant vesicles can be formed by adding inorganic salts (i.e., NaCl and NaNO 3 ), which could be derived from the membrane fusion of vesicles. The noncovalent interactions, including π-π stacking, hydrogen bonding, and electrostatic interactions, were found to be responsible for the topology evolution of assemblies. Thus, it provides an opportunity to construct smart materials through the regulation of the role of noncovalent interactions in self-assembly.

Supramolecular ionogels were prepared by self-assembly of small molecules through host-guest interaction between β-cyclodextrin (β-CD) and a room-temperature ionic liquid (IL) 3-(1-methyl-3-imidazolio)propanesulfonate-lithium bis(trifluoromethanesulfonyl)imide (MIPS-LiTFSI) which contains zwitterion MIPS. 19 F NMR and 2D ROESY 1 H NMR have been used to prove that only TFSI - is involved in the complexation. 1 H NMR, FT-IR, and comparative tests indicated that the electrostatic interaction between imidazole cation and TFSI - anion and intermolecular hydrogen bonding between three compounds also contribute to the formation of supramolecular ionogel. Ionogels with different gel-sol phase transition temperatures can be obtained by adjusting the molar ratio between β-CD and MIPS-LiTFSI. In addition, the supramolecular ionogels composed of "channel type" structural β-CD have been constructed. The ionogel with high conductivity and low activation energy open a door to new fields for special applications.

A novel photoresponsive surface active ionic liquid (SAIL) 1-(4-methyl azobenzene)-3-tetradecylimidazolium bromide ([C14mimAzo]Br) with azobenzene located in the headgroup was designed. Reversible vesicle formation and rupture can be finely controlled by photostimuli without any additives in the aqueous solution of the single-tailed ionic liquid. The photoisomerization of the azobenzene derivative was investigated by (1)H NMR and UV-vis spectroscopy. Density functional theory (DFT) calculations further demonstrate that trans-[C14mimAzo]Br has less negative interaction energy, which is beneficial to aggregate formation in water. The incorporation of trans-azobenzene group increases the hydrophobicity of the headgroup and reduces the electrostatic repulsion by delocalization of charge, which are beneficial to the formation of vesicles. However, the bend of cis-azobenzene makes the cis-isomers have no ability to accumulate tightly, which induces the rupture of vesicles. Our work paves a convenient way to achieve controlled topologies and self-assembly of single SAIL.