Controlled Release and Entrapment of Enantiomers in Self-Assembling Scaffolds Composed of β-Sheet Peptides

Supramolecular Hydrogelators and Hydrogels: From Soft Matter to Molecular Biomaterials

In this review we intend to provide a relatively comprehensive summary of the work of supramolecular hydrogelators after 2004 and to put emphasis particularly on the applications of supramolecular hydrogels/hydrogelators as molecular biomaterials. After a brief introduction of methods for generating supramolecular hydrogels, we discuss supramolecular hydrogelators on the basis of their categories, such as small organic molecules, coordination complexes, peptides, nucleobases, and saccharides. Following molecular design, we focus on various potential applications of supramolecular hydrogels as molecular biomaterials, classified by their applications in cell cultures, tissue engineering, cell behavior, imaging, and unique applications of hydrogelators. Particularly, we discuss the applications of supramolecular hydrogelators after they form supramolecular assemblies but prior to reaching the critical gelation concentration because this subject is less explored but may hold equally great promise for helping address fundamental questions about the mechanisms or the consequences of the self-assembly of molecules, including low molecular weight ones. Finally, we provide a perspective on supramolecular hydrogelators. We hope that this review will serve as an updated introduction and reference for researchers who are interested in exploring supramolecular hydrogelators as molecular biomaterials for addressing the societal needs at various frontiers.

Self-assembling peptide nanofiber scaffolds for controlled release governed by gelator design and guest size

The aim of this study was to develop controlled drug delivery by network scaffolds based on self-assembling peptide RADAFI and RADAFII. These two peptides self-assembled into interconnected nanofibrilar network structures with distinct physical morphologies. The hydrogels were also utilized for entrapment and release of some model guests, promising their future application as a drug delivery vehicle. Fickian diffusion controlled the release kinetics. Furthermore, the obtained release function was dependent on both rational design of the peptides used for hydrogel formation and choice of the entrapped molecules. On the basis of the striking different releases of these two peptide scaffolds, we suggested that guest size and lipophilicity influenced the release competitively. The release of RADAFI system was dominated by guest size, and the guest lipophilicity controlled the release behavior in RADAFII system. In a word, this work would potentially provide a spatially and temporally controlled delivery system for some functional drugs in the future.