title: New RGD-peptide amphiphile mixtures containing a negatively charged diluent.
abstract: Here, we studied the self-assembly of two peptide amphiphiles, C16-Gly-Gly-Gly-Arg-Gly-Asp (PA 1: C16-GGG-RGD) and C16-Gly-Gly-Gly-Arg-Gly-Asp-Ser (PA 2: C16-GGG-RGDS). We showed that PA 1 and PA 2 self-assemble into nanotapes with an internal bilayer structure. C16 chains were highly interdigitated within the nanotape cores, while the peptide blocks formed water-exposed 13-sheets too. PA 1 nanotapes were characterized by one spacing distribution, corresponding to a more regular internal structure than that of PA 2 nanotapes, which presented two different spacing distributions. We showed that it is possible to obtain homogeneous nanotapes in water by co-assembling PA 1 or PA 2 with the negatively charged diluent C,16-Glu-Thr-Thr-Glu-Ser (PA 3: C16-ETTES). The homogeneous tapes formed by PA 1-PA 3 or PA 2-PA 3 mixtures presented a structure similar to that observed for the corresponding pure PA 1 or PA 2 nanotapes. The mixed nanotapes, which were able to form a stabilized matrix containing homogeneously distributed cell adhesive RGD groups, represent promising materials for designing new cell adhesion substrates.
authors.forename: Valeria
authors.initials: V
authors.lastname: Castelletto
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Gouveia
authors.forename: Che J
authors.initials: CJ
authors.lastname: Connon
authors.forename: Ian W
authors.initials: IW
authors.lastname: Hamley
mesh_terms: D009842:Oligopeptides / Q000737:chemistry*; D012212:Rheology; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid