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Herein, fabrication and modification of novel bio-inspired microwell arrays with nanoscale topographic structures are reported. The natural nano- and microstructures present on the surface of rose petals were hypothesized to enhance cell-surface contacts. Thus hierarchically structured polyethylene terephthalate glycol modified (PETG) substrates were fabricated by replication from rose petals via nanoimprint lithography, followed by covalent modification and crosslinking with RGD-presenting gelatin-methacrylate (GelMA) for promoting cell adhesion and spreading. Cell culture experiments showed that the introduction of gelatin resulted in significantly enhanced cell adhesion and more than doubled cell areas on the GelMA modified surfaces. In addition, a slight preference was observed for concave compared to convex surfaces, which is tentatively attributed to the matching curvature of the micro-cavities and the cells, facilitating the accommodation of cells. These bioinspired hierarchically structured and gelatin functionalized substrates may provide new prospects for designing cell-based interfaces for advanced biomedical studies, e.g. for cell culture and biosensing in the future.

Amino acid-derived self-assembled nanofibers comprising supramolecular chiral hydrogels with unique physiochemical characteristics are highly demanded biomaterials for various biological applications. However, their narrow functionality often limits practical use, necessitating the development of biomaterials with multiple features within a single system. Herein, chiral co-assembled hybrid hydrogel systems termed LPH-EGCG and DPH-EGCG were constructed by co-assembling L/DPFEG gelators with epigallocatechin gallate (EGCG) followed by cross-linking with polyvinyl alcohol (PVA) and hyaluronic acid (HA). The developed hybrid hydrogels exhibit superior mechanical strength, self-healing capabilities, and adhesive properties, owing to synergistic non-covalent interactions. Integrating hydrophilic polymers enhances the system's capacity to demonstrate favorable swelling characteristics. Furthermore, the introduction of EGCG facilitated the hybrid gels to display notable antibacterial properties against both Gram-positive and Gram-negative bacterial strains, alongside showcasing strong antioxidant capabilities. In vitro investigation demonstrated enhanced cell adhesion and migration with the LPH-EGCG system in comparison to DPH-EGCG, thus emphasizing the promising prospects of these hybrid hydrogels in advanced tissue engineering applications. [ABSTRACT FROM AUTHOR]

Being able to precisely manipulate both the morphology and chiroptical signals of supramolecular assemblies will help to better understand the natural biological self‐assembly mechanism. Two simple l/d‐phenylalanine‐based derivatives (L/DPFM) have been designed, and their solvent‐dependent morphology evolutions are illustrated. It was found that, as the content of H2O in aqueous ethanol solutions was increased, LPFM self‐assembles first into right‐handed nanofibers, then flat fibrous structures, and finally inversed left‐handed nanofibers. Assemblies in ethanol and H2O exhibit opposite conformations and circular dichroism (CD) signals even though they are constructed from the same molecules. Thus, the morphology‐dependent cell adhesion and proliferation behaviors are further characterized. Left‐handed nanofibers are found to be more favorable for cell adhesion than right‐handed nanostructures. Quantitative AFM analysis showed that the L929 cell adhesion force on left‐handed LPFM fibers is much higher than that on structures with inversed handedness. Moreover, the value of cell Young's modulus is lower for left‐handed nanofibrous films, which indicates better flexibility. The difference in cell‐substrate interactions might lead to different effects on cell behavior. [ABSTRACT FROM AUTHOR]

Although helical nanofibrous structures have great influence on cell adhesion, the role played by chiral molecules in these structures on cells behavior has usually been ignored. The chirality of helical nanofibers is inverted by the odd-even effect of methylene units from homochiral l-phenylalanine derivative during assembly. An increase in cell adhesion on left-handed nanofibers and weak influence of cell behaviors on right-handed nanofibers are observed, even though both were derived from l-phenylalanine derivatives. Weak and negative influences on cell behavior was also observed for left- and right-handed nanofibers derived from d-phenylalanine, respectively. The effect on cell adhesion of single chiral molecules and helical nanofibers may be mutually offset. [ABSTRACT FROM AUTHOR]