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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]

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]

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]