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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]

Fabricating structural complex assemblies from simple amino acid‐based derivatives is attracting great research interests due to their easy accessibility and preparation. However, the morphological regulation of racemates (an equimolar mixture of enantiomers) were largely overlooked. In this work, through rational modulation of kinetic and thermodynamic parameters, we achieved multiple dimensional architectures employing tryptophan‐based racemate (RPWM). Upon assembling, 1D bundled nanofibers, 2D lamellar nanostructure and 3D urchin‐like microflowers could be obtained depending on the solvents used. The corresponding morphology evolutions were successfully illustrated by changing the enantiomeric excess (ee) value. Moreover, for RPWM, uniform 0D nanospheres were formed in H2O under 4 °C, which could spontaneously convert into lamella under ambient temperature. Taking advantages of its temperature‐responsive phase change behavior, RPWM assemblies exhibited excellent removal efficiency for organic dye RhB, and could be reused for several consecutive cycles without significant changes in its removal performance. Taken together, it's rational to envision that the engineering of racemates assembly pathways can greatly increase the robustness in a wide variety of supramolecular materials and further lead to their blooming versatile applications. [ABSTRACT FROM AUTHOR]

Although chiral nanostructures have been fabricated at various structural levels, the transfer and amplification of chirality from molecules to supramolecular self‐assemblies are still puzzling, especially for heterochiral molecules. Herein, four series of C2‐symmetrical dipeptide‐based derivatives bearing various amino acid sequences and different chiralities are designed and synthesized. The transcription and amplification of molecular chirality to supramolecular assemblies are achieved. The results show that supramolecular chirality is only determined by the amino acid adjacent to the benzene core, irrespective of the absolute configuration of the C‐terminal amino acid. In addition, molecular chirality also has a significant influence on the gelation behavior. For the diphenylalanine‐based gelators, the homochiral gelators can be gelled through a conventional heating–cooling process, whereas heterochiral gelators form translucent stable gels under sonication. The racemic gels possess higher mechanical properties than those of the pure enantiomers. All of these results contribute to an increasing knowledge over control of the generation of specific chiral supramolecular structures and the development of new optimized strategies to achieve functional supramolecular organogels through heterochiral and racemic systems. [ABSTRACT FROM AUTHOR]

In the section of "RPWM assembles in ethanol/H SB 2 sb O (1/9)", seventh paragraph, the description given is "High-resolution TEM (HRTEM) and select area electron diffraction (SAED) further confirmed the crystalline structure of RPWM assemblies (Figure S5a and c)" and should now be "High-resolution TEM (HRTEM) further confirmed the crystalline structure of RPWM assemblies (Figure S5a)". The diffraction spots in the SAED data correspond specifically to the interplanar spacing of the assemblies, however, not correctly to certain lattice parameters. The HRTEM images clearly showed the interplanar spacing of the assemblies, demonstrating their crystalline structures. [Extracted from the article]