Chirality from D-guanosine to L-guanosine shapes a stable gel for three-dimensional cell culture

It is proved that L-guanosine (L-G) as an enantiomer of D-guanosine (D-G) forms more stable gels than D-G, suggesting that alteration of chirality may be a new strategy for improving the lifetime stability of supramolecular hydrogels. Experiments for three-dimensional cell culture reveal that the L-G gel is a candidate for the extracellular matrix.

The formation of the salt and neutral molecule cocrystal from equimolar solution of heliamine and bicyclo[2.2.1]hept-5-ene-endo-2,3-dicarboxylic acid

The possible interaction of 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (heliamine) with bicyclo[2.2.1]hept-5-ene-endo-2,3-dicarboxylic acid anhydride has been studied. Instead of the reaction with heliamine, the acid anhydride was hydrolyzed into the appropriate dicarboxylic acid. An equimolar mixture of unreacted heliamine and in-situ-generated dicarboxylic acid crystallized in space group P2₁/c. The comprehensive study of the obtained crystals shows that the peculiarities of the crystallization process lead to the formation of the salt-cocrystal structure where the dianion interacts simultaneously with two cations forming a chain as the primary structural motif. The neutral molecules of dicarboxylic acid link the dianions of the neighbouring chains, forming a layer as the secondary structural motif. As a result, the stronger hydrogen bonds formed by the neutral molecules play a secondary role in the crystal structure formation.

Dynamics of formation of Ru, Os, Ir and Au metal nanocrystals on doped graphitic surfaces

The fabrication of precious metal (ruthenium, osmium, gold, and iridium) nanocrystals from single atoms has been studied in real-time.

Supramolecular Hydrogelators and Hydrogels: From Soft Matter to Molecular Biomaterials

In this review we intend to provide a relatively comprehensive summary of the work of supramolecular hydrogelators after 2004 and to put emphasis particularly on the applications of supramolecular hydrogels/hydrogelators as molecular biomaterials. After a brief introduction of methods for generating supramolecular hydrogels, we discuss supramolecular hydrogelators on the basis of their categories, such as small organic molecules, coordination complexes, peptides, nucleobases, and saccharides. Following molecular design, we focus on various potential applications of supramolecular hydrogels as molecular biomaterials, classified by their applications in cell cultures, tissue engineering, cell behavior, imaging, and unique applications of hydrogelators. Particularly, we discuss the applications of supramolecular hydrogelators after they form supramolecular assemblies but prior to reaching the critical gelation concentration because this subject is less explored but may hold equally great promise for helping address fundamental questions about the mechanisms or the consequences of the self-assembly of molecules, including low molecular weight ones. Finally, we provide a perspective on supramolecular hydrogelators. We hope that this review will serve as an updated introduction and reference for researchers who are interested in exploring supramolecular hydrogelators as molecular biomaterials for addressing the societal needs at various frontiers.