The fiber formation of amyloid beta peptides is known to be an essential step of fibrillogenesis, the hallmark mechanism of Alzheimer's disease. Two types of amyloid beta which are critical in the mechanism of Alzheimer's disease are a hydrophilic amyloid beta of sequences 1-40 and a hydrophobic amyloid beta of sequences 1-42. Both A�1-40 and A�1-42 do not show a reversible self-assembly in a dimethyl sulfoxide environment when they are directly placed over a gold colloidal surface. However, both the hydrophilic and hydrophobic amyloid beta exhibited a reversible self-assembly when they were attached over a series of dibezyloxy disulfide functionalized gold colloids. The surface of the gold colloids was functionalized with a series of dibenzyloxy disulfides containing chloro-, methoxy-, phenyl, and nitro-substituents in the para position, and  the reversible self-assembly process of each case was examined. Out of the above functionalizing groups, the methoxy-substituent exhibited a significant enhancement in the reversible self-assembly process.  In addition, the adsorptions of A�1-40 and A�1-42 were examined by the shift of pH0, i.e., the pH value where the color of the solution changes.  The smallest pH0 shift was observed when the methoxy-substituent was used.  This implies that a functionalized gold did not disturb the conformation of amyloid beta.

Reversible self-assembly of amyloid beta 1-40 and amyloid beta 1-42 peptides over functionalized gold colloids

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.