The control and prediction of the self-assembly process in multicomponent supramolecular gels are challenging because the structure and properties rely mostly on the geometry and spatial arrangement of the building blocks. The understanding of noncovalent interactions between the individual gelators at the molecular level will enable us to tune the gelation properties of multicomponent gels. We have studied the self-assembly process of multicomponent gel based on enantiomers and herin we report the first crystallographic evidence of specific co-assembly in mixed enantiomeric gel, which is supported by scanning electron microscopy and atomic force microscopy images. The mode of interactions between the individual gelators from the molecular to macroscopic level, which are responsible for co-assembled fibers, was identified by single-crystal X-ray diffraction. We have proved that specific co-assembly leads to enhanced mechanical and thermal stability in the mixed gel compared to the meso and individual enantiomeric gels.

To investigate the role of the capping group in the solution and solid-state self-assembly of short peptide amphiphiles, dialanine and diphenylalanine have been linked via the N-terminus to a benzene (phenyl) and 3-naphthyl capping groups using three different methylene linkers; (CH 2 ) n , n = 0-4 for the benezene and 0, 1 and 2 for the naphthalene capping group. Atomic force microscopy (AFM), oscillatory rheology, circular dichroism (CD), and IR analysis have been employed to understand the proper-ties of these peptide-based hydrogels. Several X-ray structures of these short peptide gelators give useful conformational information regarding packing. A comparison of these solid state structures with their gel state properties yielded greater insights into the process of self-assembly in short peptide gelators, particularly in terms of the important role of C···H interactions appear to play in determining if a short aromatic peptide does form a gel or not.[a] Dr.

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