Interaction of β-Amyloid Interactions with Peptide Functionalized Gold Nanoparticles

The physicochemical properties of gold nanoparticles (GNPs) functionalized with peptides and N-methylated peptides were studied with respect to their interaction with β-amyloid (1–42). Peptides with sequences of CGGIGLMVG and CGGGGGIGLMVG linked with GNPs of an average diameter of 13 nm were employed for this study. The peptide-GNPs were found to be soluble and dispersed at pH 7.4 in a sodium phosphate aqueous buffer solution. The resonance spectra of each peptide coated GNP was measured in the absence and presence of β-amyloid (1–42). The difference in the intensity of the λ_max of the resonance absorption bands was attributed to the interaction of the functionalized GNPs with the protein. Particles bearing the CGGGGGIGLMVG sequence exhibited the largest change in λ_max intensity; the prevention of fibril formation and inhibition of cytotoxicity was also examined.