Solvent‐ and Substrate‐Induced Chiroptical Inversion in Amphiphilic, Biocompatible Glycoconjugate Supramolecules: Shape‐Persistent Gelation, Self‐Healing, and Antibacterial Activity

We have shown solvent‐ and substrate‐dependent chiral inversion of a few glycoconjugate supramolecules. (Z)‐F‐Gluco, in which d‐glucosamine has been attached chemically to Cbz‐protected l‐phenylalanine at the C terminus, forms a self‐healing hydrogel through intertwining of the nanofibers wherein the gelators undergo lamellar packing in the β‐sheet secondary structures with a single chiral handedness. Dihybrid (Z)‐F‐gluco nanocomposite gel was prepared by in‐situ formation of silver nanoparticles AgNPs in the gel; this enhances the mechanical properties of the composite gel through physical crosslinking without altering the packing pattern. In contrast, (Z)‐L‐gluco bearing an l‐leucine moiety does not form a hydrogel but an organogel. Interestingly, the chiral handedness of the aggregates of (Z)‐L‐gluco can be reversed by choosing suitable solvents. In addition to self‐healing behavior, (Z)‐L‐gluco gel revealed shape persistency. Further, (Z)‐F‐gluco hydrogel is benign, nontoxic, non‐immunogenic, and non‐allergenic in animal cells. AgNP‐loaded (Z)‐F‐gluco hydrogel showed antibacterial activity against both Gram‐positive and Gram‐negative bacteria. Sometimes things just gel: Glycoconjugate (Z)‐F‐gluco in which a d‐glucosamine moiety was attached to Cbz‐protected l‐phenylalanine at the C terminus showed hierarchical self‐aggregation leading to the formation of transparent, injectable, and biocompatible hydrogel. (Z)‐F‐Gluco nanocomposite hydrogel bearing AgNPs can be applied topically as an antibacterial soft material. Solvent‐dependent chiral inversion was demonstrated in the aggregates of a (Z)‐L‐gluco‐bearing l‐leucine unit.