Mechanical Properties of Self-Assembled Fmoc-Diphenylalanine Molecular Gels

Abstract

We explore the phase diagram and mechanical properties of molecular gels produced from mixing water with a dimethyl sulfoxide (DMSO) solution of the aromatic dipeptide derivative fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF). Highly soluble in DMSO, Fmoc-FF assembles into fibrous networks that form gels upon addition of water. At high water concentrations, rigid gels can be formed at Fmoc-FF concentrations as low as 0.01 wt %. The conditions are established defining the Fmoc-FF and water concentrations at which gels are formed. Below the gel boundary, the solutions are clear and colorless and have long-term stability. Above the gel boundary, gels are formed with increasing rapidity with increasing water or Fmoc-FF concentrations. A systematic characterization of the effect of Fmoc-FF and water concentrations on the mechanical properties of the gels is presented, demonstrating that the elastic behavior of the gels follows a specific, robust scaling with Fmoc-FF volume fraction. Furthermore, we characterize the kinetics of gelation and demonstrate that these gels are reversible in the sense that they can be disrupted mechanically and rebuild strength over time.

Tuning of hydrogel stiffness using a two‐component peptide system for mammalian cell culture

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Structural Characterization of Self‐Assembled Tetra‐Tryptophan Based Nanostructures: Variations on a Common Theme

“…These findings suggest the possibility to design novel peptide based materials with enhanced properties. By this evidence, many structural analogues of diphenylalanine (like WF, LF, FFF, FFFF, di‐3,4‐dihydroxyphenylalanine and Fmoc‐FF) and their PEGylated‐polymer conjugates have been reported …”

Amyloid‐Like Fibrillary Morphology Originated by Tyrosine‐Containing Aromatic Hexapeptides

“…The high cytocompatibility detectedi nv itro can be probably attributed to the hydrogel preparation method that, contrarily to others peptideh ydrogels, does not require the employment of any organic solvents (like DMSO, HFIP,orM eOH). [36]…”