Supramolecular assembly based on aromatic interactions can provide well-defined nanostructures with an understanding of intermolecular interactions at the molecular level. The peptide assembly via a supramolecular approach can overcome the inherent limitations of bioactive peptides, such as proteolytic degradations and rapid internalizations into the cytosol. Although extensive research has been carried out on supramolecular peptide materials with a two-dimensional (2D) structure, more needs to be reported on biological activity studies using well-defined 2D peptide materials. Physical and chemical properties of the 2D peptide assembly attributed to their large surface area and flexibility can show low cytotoxicity, enhanced molecular loading, and higher bioconjugation efficiency in biological applications. Here, we report supramolecular 2D materials based on the pyrene-grafted amphiphilic peptide, which contains a peptide sequence (Asp-Gly-Glu-Ala; DGEA) that is reported to bind to the integrin α2β1 receptor in 2D cell membranes. The addition of octafluoronaphthalene (OFN) to the pyrene-grafted peptide could induce a well-ordered 2D assembly by face-centered arene–perfluoroarene stacking. The DGEA-peptide 2D assembly with a flat structure, structural stability against enzymatic degradations, and a larger size can enhance the proliferation and differentiation of muscle cells via continuous interactions with cell membrane receptors integrin α2β1 showing a low intracellular uptake (15%) compared to that (62%) of the vesicular peptide assembly. These supramolecular approaches via the arene–perfluoroarene interaction provide a strategy to fabricate well-defined 2D peptide materials with an understanding of assembly at the molecular level for the next-generation peptide materials.

Variations in the functionalities of materials of different dimensions containing the same functional groups can be attributed to the structural stability and morphology of the materials. The morphology of peptide assemblies can influence their interactions with biological systems and ultimately modulate their bioactivity. Among reported Arg-Gly-Asp (RGD)-based supramolecular materials, two-dimensional (2-D) peptide assembly has been rarely studied. Herein, we report the fabrication of RGD-based supramolecular one-dimensional (1-D) and 2-D assemblies as peptide-based myoblast growth accelerators. The 2-D assembly was more effective in proliferating C2C12 cells than the 1-D assembly. These findings provide insights into the construction of optimal RGD-based supramolecular functional materials of different dimensions.

Cell chirality plays a critical role in the linkage between molecular chirality and the asymmetrical biological functions of body organs. However, enantioselective interactions between cell chirality and the extracellular environment are not yet fully understood. In this study, we investigated the effects of structurally chiral extracellular microenvironments on cellular alignments and differentiations. Twisted wrinkle-shaped chiral micropatterns were prepared using biaxial and asymmetric buckling methods, wherein structural handedness was determined from the orientation of the tilt angle between the first and second microwrinkles. Myoblasts were separately cultured on two enantiomeric chiral micropatterns in a mirror-reflected shape. Cells cultured on the left-handed chiral micropatterns preferred alignments along the direction of the second microwrinkle, with a relatively deeper valley than that of the first microwrinkle. The aligned cells on the left-handed pattern showed higher differentiation rates, as assessed by fusion indices and marker protein expression levels, than those cultured on right-handed chiral micropatterns. These results suggest that myoblasts exhibit enantioselective recognition of structurally chiral microenvironments, which can promote cellular alignments and differentiation.

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