title: Hierarchical Analysis of Self-Assembled PEGylated Hexaphenylalanine Photoluminescent Nanostructures.
abstract: Despite the growing literature about diphenylalanine-based peptide materials, it still remains a challenge to delineate the theoretical insight into peptide nanostructure formation and the structural features that could permit materials with enhanced properties to be engineered. Herein, we report the synthesis of a novel peptide building block composed of six phenylalanine residues and eight PEG units, PEG8-F6. This aromatic peptide self-assembles in water in stable and well-ordered nanostructures with optoelectronic properties. A variety of techniques, such as fluorescence, FTIR, CD, DLS, SEM, SAXS, and WAXS allowed us to correlate the photoluminescence properties of the self-assembled nanostructures with the structural organization of the peptide building block at the micro- and nanoscale. Finally, a model of hexaphenylalanine in aqueous solution by molecular dynamics simulations is presented to suggest structural and energetic factors controlling the formation of nanostructures.
authors.affiliation: Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II" and DFM Scarl, Via Mezzocannone 16, 80134, Naples, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Diaferia
authors.affiliation: Institute of Crystallography (IC), CNR, Via Amendola 122, 70126, Bari, Italy.
authors.forename: Teresa
authors.initials: T
authors.lastname: Sibillano
authors.affiliation: Institute of Biostructures and Bioimaging (IBB), CNR, Via Mezzocannone 16, 80134, Naples, Italy.
authors.forename: Nicole
authors.initials: N
authors.lastname: Balasco
authors.affiliation: Institute of Crystallography (IC), CNR, Via Amendola 122, 70126, Bari, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Giannini
authors.affiliation: Regional Center of Competence Technologies Scarl, Via Nuova Agnano, 11, 80125, Naples, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Roviello
authors.affiliation: Institute of Biostructures and Bioimaging (IBB), CNR, Via Mezzocannone 16, 80134, Naples, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Vitagliano
authors.affiliation: Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II" and DFM Scarl, Via Mezzocannone 16, 80134, Naples, Italy.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Morelli
authors.affiliation: Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II" and DFM Scarl, Via Mezzocannone 16, 80134, Naples, Italy. Antonella.accardo@unina.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: Accardo
keywords: diphenylalanine; molecular dynamics; nanostructures; peptide materials; photoluminescence