How should multicomponent supramolecular gels be characterised?

Abstract

Low molecular weight gels, or supramolecular gels, are formed when small molecules self-assemble into fibrous structures. Above a critical concentration, the entanglement and cross-linking of these structures leads to the formation of a self-supporting gel. There are many examples where a single component is used to form such gels. There is however an ever-increasing interest in using multiple components. Here, if each component is able to form a gel by itself, a range of fibre types are possible, formed by either random or specific associations between the low molecular weight gelators (LMWG). The properties of the networks will depend on how the LMWG assemble into the primary fibrous structures and then how these primary structures entangle. As such, to understand these gels, it is necessary to understand the networks across multiple length scales. Here, we discuss the current state of the art, the effectiveness of the different techniques that have been used, and hopefully provide the impetus for the field to move away from the cartoon-level discussion of assembly.

The Power of Confocal Laser Scanning Microscopy in Supramolecular Chemistry: In situ Real‐time Imaging of Stimuli‐Responsive Multicomponent Supramolecular Hydrogels

“…To date, spectroscopic methods including circular dichroism (CD), absorbance, and fluorescent spectroscopy have been widely used, particularly to evaluate molecular packing in the nanofibers. [10] However, these spectroscopic analyses give only ensemble (average) structural information. Microscopy methods such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) are able to visualize individual nanofiber shapes at nanometer resolution.…”

Hybrid Soft Nanomaterials Composed of DNA Microspheres and Supramolecular Nanostructures of Semi‐artificial Glycopeptides

“…Orthogonal self-assemblyo fp lurals upramolecular nanostructures, which are reminiscent of complex biological supra-(macro)molecular systems, entailt he self-assembly of multiple constituent monomeric moleculest of orm distinct supramolecular nanostructures. [1] The scope for constructing such complex and discrete soft matterf rom diverses upramolecular nanostructuresi nasingle aqueous medium is gradually advancing. For example, using artificially designed small molecules, van Esch and co-workersh ave demonstratedt he orthogonal coexistence of supramolecular fibers (constructed from self-assembling small molecules through hydrogen-bondingi nteractions and van der Waals interactions)a nd micelles and/or vesicles (constructed from conventional amphiphiles).…”

Programmable Multicomponent Self‐Assembly Based on Aromatic Amino Acids

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