Photoresponsive supramolecular gels based on amphiphiles with azobenzene and maltose or polyethyleneglycol polar head

Clemente, María J.; Tejedor, Rosa M.; Romero, Pilar; Fitremann, Juliette; Oriol, Luis

doi:10.1039/c4nj02012j

Cited by 22 publications

(15 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The photoresponsive liquid crystalline gels formed by the hydrogen-bond self-organization between the barbiturate and azobenzene appended melamine were specifically investigated in terms of the mechanism and behavior of self-organization due to the exotic rosette structure. [101,103] The tridedocyloxyphenyl promoted steric stacking of the complexes to generate a columnar liquid crystalline gel in the bulky state, while such state was not observed in aliphatic solvent due to weakening of the aggregation. Therefore, the barbiturate component was replaced with N-dodecylcyanurate with enhanced steric stacking, resulting in a hexagonal columnar liquid crystalline gel in a face-to-face arrangement manner.…”

Section: Photoresponsive Gelsmentioning

confidence: 99%

“…An amphiphilic chiral azobenzene‐based gel was designed, connecting the long hydrophobic alkoxy on one side of azobenzene and the hydrophilic maltose or polyethyleneglycol (PEG) on the other side. [ 103 ] Left‐handed phenylalanine was linked to provide the gel with chirality. The molecular weight of the terminal PEG determined the formation of gel in solutions, that is, a smaller molecular weight promoted the generation of the gel in either dimethylsulfoxide or aqueous solution; while a larger weight tended to form a fibrous helix in the water.…”

Section: Photoresponsive Chiro‐optical Mesogenic Helical Soft Materialsmentioning

confidence: 99%

See 1 more Smart Citation

Photoprogrammable Mesogenic Soft Helical Architectures: A Promising Avenue toward Future Chiro‐Optics

Zheng

2020

Advanced Materials

View full text Add to dashboard Cite

reflection, exhibits photonic localization in the band gap determined by the period in the case of normal incidence. [6] Similarly, a helical superstructure composed of chiral chromophores leads to absorption differences between left-and right-handed CPL, referred to as the Cotton effect, owing to the asymmetry of chiral chromophores or that of achiral chromophores induced by a chiral system. [7] Chiro-optical characteristics in helical supramolecular assemblies and superstructures have attracted tremendous attention in the past decade, especially in self-organized mesogenic helical soft matter, which is an emerging scientific frontier in chemistry, functional materials, soft matter physics, biological medicine, and even sensor physics. Mesogenic soft matter, defined as soft condensed matter with molecules containing single or multiple anisotropic mesogen moieties, is distinct from common soft condensed matter in terms of molecular arrangement, interaction, and specific optical chirality, although the "soft" characteristic is still maintained. A primary reason for the softness is related to the responses of this type of matter to multiple external stimuli, such as electric fields, heat, light, mechanical forces, and even acoustic fields. [8] The control and manipulation of such soft materials by light is always more desirable than that of other stimuli due to the prominent advantages of non-contact, wireless, remote, and high-resolution control, which enable numerous unprecedented chiro-optical applications. [9] Optically, another fascinating feature of these materials is their molecular self-organization behavior, which can establish an ordered and regular arrangement with a structural parameter (≈µm) much larger than the single-molecule scale (≈nm) through the weak non-covalent molecular interaction, rather than the chemical bonds that normally exist in

show abstract

Section: Photoresponsive Gelsmentioning

confidence: 99%

Section: Photoresponsive Chiro‐optical Mesogenic Helical Soft Materialsmentioning

confidence: 99%

Photoprogrammable Mesogenic Soft Helical Architectures: A Promising Avenue toward Future Chiro‐Optics

Zheng

2020

Advanced Materials

View full text Add to dashboard Cite

show abstract

“…Oriol and coworkers have designed and synthesized several amphiphilic compounds containing azobenzene as a photosensitive unit, PEG or maltose as the polar head groups and l -phenylalanine as the linker [100]. Of these, the maltose derived amphiphile (Malt-Phe-Azo-C 18 , 34a , Figure 22), and except PEG 16 -, all other PEG-derived amphiphiles were proved to be efficient photoresponsive organogelators.…”

Section: Applicationsmentioning

confidence: 99%

Carbohydrate Derived Organogelators and the Corresponding Functional Gels Developed in Recent Time

Basu¹,

Chakraborty

Ghosh

2018

Gels

View full text Add to dashboard Cite

Owing to their multifarious applicability, studies of molecular and supramolecular gelators and their corresponding gels have gained momentum, particularly in the last two decades. Hydrophobic-hydrophilic balance, different solvent parameters, gelator-gelator and gelator-solvent interactions, including different noncovalent intermolecular interactive forces like H-bonding, ionic interactions, π-π interactions, van der Waals interactions, etc., cause the supramolecular gel assembly of micro and nano scales with different types of morphologies, depending on the gelator, solvent, and condition of gelation. These gel structures can be utilized for making template inorganic superstructures for potential application in separation, generation of nanocomposite materials, and other applications like self-healing, controlled drug encapsulation, release and delivery, as structuring agents, oil-spill recovery, for preparation of semi-conducting fabrics, and in many other fields. Sugars, being easily available, inexpensive, and nontoxic natural resources with multi functionality and well-defined chirality are attractive starting materials for the preparation of sugar-based gelators. This review will focus on compilation of sugar derived organogelators and the corresponding gels, along with the potential applications that have been

show abstract

“…In former results, a family of hydrogelators based on a disaccharide head has been described. It has been shown that the presence of a triazole linker enhanced gelation, but the synthetic pathway consisted of six steps [23][24][25][26]. Other amphiphilic molecules with close structures (namely, a sugar head, triazole linkers, and a fatty chain) have been described as well, including hydrogelators [27][28][29], organogelators [30] and micelles [31][32][33], all of them involving also protection-deprotection multistep synthesis and purification by chromatography.…”

Section: Introductionmentioning

confidence: 99%

A shear-induced network of aligned wormlike micelles in a sugar-based molecular gel. From gelation to biocompatibility assays

Fitremann

Lonetti

Fratini

et al. 2017

Journal of Colloid and Interface Science

Self Cite

View full text Add to dashboard Cite

A new low molecular weight hydrogelator with a saccharide (lactobionic) polar head linked by azide-alkyne click chemistry was prepared in three steps. It was obtained in high purity without chromatography, by phase separation and ultrafiltration of the aqueous gel. Gelation was not obtained reproducibly by conventional heating-cooling cycles and instead was obtained by shearing the aqueous solutions, from 2 wt% to 0.25 wt%. This method of preparation favored the formation of a quite unusual network of interconnected large but thin 2D-sheets (7nm-thick) formed by the association side-by-side of long and aligned 7nm diameter wormlike micelles. It was responsible for the reproducible gelation at the macroscopic scale. A second network made of helical fibres with a 10-13nm diameter, more or less intertwined was also formed but was scarcely able to sustain a macroscopic gel on its own. The gels were analysed by TEM (Transmission Electronic Microscopy), cryo-TEM and SAXS (Small Angle X-ray Scattering). Molecular modelling was also used to highlight the possible conformations the hydrogelator can take. The gels displayed a weak and reversible transition near 20°C, close to room temperature, ascribed to the wormlike micelles 2D-sheets network. Heating over 30°C led to the loss of the gel macroscopic integrity, but gel fragments were still observed in suspension. A second transition near 50°C, ascribed to the network of helical fibres, finally dissolved completely these fragments. The gels showed thixotropic behaviour, recovering slowly their initial elastic modulus, in few hours, after injection through a needle. Stable gels were tested as scaffold for neural cell line culture, showing a reduced biocompatibility. This new gelator is a clear illustration of how controlling the pathway was critical for gel formation and how a new kind of self-assembly was obtained by shearing.

show abstract

Photoresponsive supramolecular gels based on amphiphiles with azobenzene and maltose or polyethyleneglycol polar head

Abstract: Photoresponsive supramolecular gelators have been synthesized using PEG or d-maltose as polar head. Incorporation of azobenzene photoresponsive moieties allows controlling the supramolecular gel structure, including a reversible gel–sol transition using light as external stimulus.

Cited by 22 publications

References 41 publications

Photoprogrammable Mesogenic Soft Helical Architectures: A Promising Avenue toward Future Chiro‐Optics

Photoprogrammable Mesogenic Soft Helical Architectures: A Promising Avenue toward Future Chiro‐Optics

Carbohydrate Derived Organogelators and the Corresponding Functional Gels Developed in Recent Time

A shear-induced network of aligned wormlike micelles in a sugar-based molecular gel. From gelation to biocompatibility assays

Contact Info

Product

Resources

About