Interactions of amyloid Aβ(1-42) peptide with self-assembled peptide nanospheres.

In this work we have probed the interactions of the amyloid Aβ(1-42) peptide with self-assembled nanospheres. The nanospheres were formed by self-assembly of a newly developed bolaamphiphile bis(N-alpha-amido-methionine)-1,8 octane dicarboxylate under aqueous conditions. It was found that the interactions of the Aβ(1-42) peptide with the nanospheres were concentration as well as pH dependent and the peptide largely adopts a random coil structure upon interacting with the nanospheres. Further, upon incorporation with the nanospheres, we observed a relative diminution in the aggregation of Aβ(1-42) at low concentrations of Aβ(1-42). The interactions between the nanospheres and the Aβ(1-42) peptide were investigated by atomic force microscopy, transmission electron microscopy, circular dichroism, FTIR and fluorescence spectroscopy, and the degree of fibrillation in the presence and absence of nanospheres was monitored by the Thioflavine T assay. We believe that the outcome from this work will help further elucidate the binding properties of Aβ peptide as well as designing nanostructures as templates for further investigating the nucleation and fibrillation process of Aβ-like peptides.