Peptide aggregation in amyloid fibrils is implicated in the pathogenesis of several diseases such as Alzheimer's disease. There is a strong correlation between amyloid fibril formation and a decrease in conformational stability of the native state. Amyloid-P peptide (A beta), the aggregating peptide in Alzheimer's disease, is natively unfolded. The deposits found in Alzheimer's disease are composed of A beta fibrillar aggregates rich in beta-sheet structure. The influence of fluorinated complexes on the secondary structure and fibrillogenesis of A beta peptide was studied by circular dichroism, (CD) spectroscopy and transmission electron microscopy (TEM). CD spectra show that complexes of polyampholyte and fluorinated dodecanoic acid induce alpha-helix structure in A beta, but their hydrogenated analogous lead to beta-sheet formation and aggregation, The fluorinated nanoparticles with highly negative zeta potential and hydrophobic fluorinated core have the fundamental characteristics to prevent: A beta fibrillogenesis. (c) 2008 Elsevier B.V. All rights reserved.