The spontaneous assembly of nanoscale building blocks into continuous semipermeable membranes is a key requirement for the structuration of synthetic protocells.Engineering the functionality and programmability of these building units provides a step towards more complex cell-like entities with adaptive membrane properties. Inspired by the central role of protein (lectin)-carbohydrate interactions in cellular recognition and adhesion, we fabricate semipermeable polysaccharide-polymer microcapsules (polysaccharidosomes) with intrinsic lectinbinding properties. We employ amphiphilic polysaccharide-polymer membrane building blocks endowed with intrinsic bio-orthogonal lectin-glycan recognition sites to facilitate the reversible non-covalent docking of functionalized polymer or zeolitic nanoparticles on the polysaccharidosomes. We show that the programmed attachment of enzyme-loaded nanoparticles

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Having control over the supramolecular chirality through multiexternal stimulators provides many possibilities in realizing functional chiral materials. Herein, the supramolecular chirality of nanotwists comprising PA centered with 1,4-phenyldicarboxamide bearing two l/d-helicogenic alanine motifs and achiral COOH at each terminus of the alanine arms is modulated by solvent, temperature, and ultrasound. The modulations are mainly due to the hydrogen bonds among gelators and solvent-gelator interactions, resulting in changes of the molecular arrangement and subsequent self-assembled nanostructures. Typically, the gel of PA in ethyl acetate prepared by ultrasonication method exhibits thixotropic property due to the participation of ethyl acetate in the self-assembly process, resulting in relatively flexible and tolerant networks. This study provides a simplistic way to control the handedness of chiral nanostructures and a rational design of the self-assembly system with multistimuli-responsive supramolecular chirality.

Hydrazide derivatives are known to display a wide range of biological properties including antimicrobial activities, hence making them desirable candidates for soft biomaterials. Herein, we report chiral supramolecular coassembled hydrogels obtained from two phenylalanine gelators (L/DPF and B2L/D) and two dicarbohydrazide molecules (pyridine-2,6-dicarbohydrazide (PDH) and (2,2′-bipyridine)-5,5′-dicarbohydrazide (BDH)) that exhibited enhanced mechanical properties, chirality modulation, and antimicrobial activity. Four lines of coassembled hydrogels were obtained (i.e., L/DPF–PDH, L/DPF–BDH, B2L/D–PDH, and B2L/D–BDH) through hydrogen bonding and π–π stacking with some level of an interpenetrating network, as revealed by the structural characterization analysis. Mechanical properties were significantly improved, especially in the case of hybrid gels involving BDH, with improved average elastic modulus (G′) values of 3430 and 3167 Pa for DPF–BDH and B2D–BDH (1:3, molar concentration) over 140 and 1680 Pa for DPF and B2D gelators, respectively. This was attributed to the improved π–π stacking and interpenetrating network due to the bipyridine group and its ease to form fibrous precipitates in the process of heating and cooling to room temperature. PDH, on the other hand, was able to modulate chirality in the L/DPF gelator due to its more planar and less bulky nature and showed antimicrobial activity against Pseudomonas aeruginosa (Gram-negative). Interestingly, when PDH was coassembled with the B2L/D gelator, the hybrid gels exhibited antimicrobial activity against Staphylococcus aureus (Gram-positive) and P. aeruginosa (Gram-negative) by virtue of a synergistic effect of the gelator and the azomethine group of PHD. Hence, by moving from bipyridine (BDH) to pyridine (PDH) as a core structure in the hydrazide molecules, the resulting hybrid hydrogels exhibited desirable properties of antimicrobial activity and improved mechanical attributes.

Tuning of the viscoelastic properties of supramolecular hydrogels to be used as biological material substrates in tissue engineering has become significantly relevant in recent years due to their ability to influence cell fate. In the quest to enhance the stability and mechanical properties of a derived C2-phenylalanine gelator (LPF), derivatives of the polysaccharide dextran were incorporated as additives to promote hydrogen bonding and π−π stacking with the gelator. Dextran was esterified to yield carboxymethyl dextran (CMDH), which was subsequently amidated to furnish amino dextran (AD), the resulting hybrid hydrogels were denoted as LPF-AD x and LPF-CMDH x , where x represents the amount of AD and CMDH (mg). The LPF gelator interacted with the carboxyl and amino functional groups of the CMDH and AD, respectively, through hydrogen bonding and π−π stacking, resulting in mechanically stable hydrogels. Morphological studies revealed that the hybrid hydrogels were formed as a result of dense highly branched thin and broad fibers for LPF-AD and LPF-CMDH, respectively. Rheological studies confirmed the superiority of the hybrid hydrogels over the neat hydrogel, where LPF-CMDH 3 exhibited the best mechanical properties with an improved elastic modulus of 11 654 Pa over 1518 and 140 Pa for LPF-AD 4.5 and LPF, respectively. The adhesion and spreading behavior of NIH 3T3 fibroblast cells were significantly improved on the LPF-CMDH 3 substrate owing to their enhanced mechanical properties. The tuning of the mechanical properties of the therein hydrogels via the facile incorporation of biodegradable and biocompatible functionalized additives opens up avenues for strengthening the supposed weak supramolecular gelators and hence increasing their potential of being employed largely in the field of tissue engineering.

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Photoresponsive supramolecular gels as intelligent non-invasive responsive materials can undergo changes in color, state, morphology and electronic properties upon photo irradiation, making them attractive for a variety of applications. Herein, a novel supramolecular hydrogelator DBE with 1,4-divinylbenzene as the central core, connected via amide linkage to l-phenylalanine and peripheral hydrophilic groups, was designed to evaluate the effect of [2 + 2] photocycloaddition reaction on supramolecular hydrogels. UV irradiation decreases the solubility of the hydrogelator DBE and hence, causes the destruction of the gel. SEM images clearly show that irradiation with UV light could induce disintegration of the right-handed helical nanofibers entangled network, which turns into nanoparticles and eventually massive crystals. Circular dichroism and vibrational circular dichroism data also indicate the formation of right-handed helical nanofibers in DBE gel. FTIR and MALDI-TOF-MS spectrum confirm that the variation of stability and aggregated morphology of DBE gel after UV irradiation is attributed to [2 + 2] cycloaddition reaction of vinyl units. This study presents a wonderful model for regulating the stability and aggregated morphology of supramolecular hydrogels via photo irradiation, as well as offers new ideas for designing novel photo responsive materials.