Graphene & Graphene Oxide and amyloid peptide binding and its implications in Alzheimer’s disease

Abstract

Alzheimer’s disease is a neurodegenerative disease caused by the incorrect cleaving of the transmembrane Amyloid Precursor Protein into the neurotoxic Aβ40 and Aβ42 fragments2. These fragments are soluble oligomers with a random coil conformation that can impair synapses or neurotransmission; they may also aggregate into parallel and antiparallel beta sheets to form amyloid plaques, which can block or distort signaling between neuronal pathways7. Aβ fibrils self-assemble into parallel and antiparallel beta sheets on hydrophobic graphite, but not on hydrophilic mica5,6. Aβ fibrils also assemble on graphene, which irreversibly captures fibrils3, suggesting grapheme might have a role in the study of Alzheimer’s amyloid plaque. These studies characterize binding between amyloid beta peptide fibrils and graphene using Raman spectroscopy, scanning electron microscopy (SEM), and circular dichroism (CD). The goal is to provide evidence that graphene can attract free floating Aβ fibrils and Aβ plaque. Both studies currently use diphenylalanine peptide, a self-assembling model peptide for Aβ fibrils.