A supramolecular KLVFF/graphene oxide/cyclodextrin assembly for selective recognition of amyloid β 42 peptide

Early diagnosis can greatly improve quality of life in patients affected by severe diseases such as Alzheimer's (AD). Therefore, the development of alternative platforms for the improvement of clinical diagnostic methods is gaining increasing interest. In this scenario, nanotechnology offers the opportunity to design and tailor materials and devices on purpose. Following this lead, graphene oxide (GO) flakes were decorated with amphiphilic cyclodextrin heptakis[6-deoxy-6-hexadecylthio-2-poly(ethyleneglycol)]-β-cyclodextrin (SC16OH) nanovesicles entangling the hydrophobic peptide conjugate ferrocenyl-(PEG)₄-KLVFF (Lys-Leu-Val-Phe-Phe, Aβ (16-20)). This supramolecular assembly, whose structural features enable electrochemical platforms to recognize the Aβ42 peptide, was characterized using spectroscopic and analytical techniques including cyclic voltammetry (CV), Fourier transform Infrared spectroscopy (FT-IR), circular dichroism (CD) and scanning electron microscopy (SEM). The interaction between the proposed platform and various Aβ peptides, such as Aβ42, Aβ40 scrambled (Aβ40s) and Aβ42 scrambled (Aβ42s) isoforms, was evaluated by CV pointing out specific and concentration-dependent recognition toward Aβ42.