Self-Assembly of Dyestuffs and Proteins

Numerous synthetic, low molecular weight compounds like organic azo-dyestuffes form fiber-like aggregates in aqueous solution in close analogy to the self-assembly of various proteins in living systems. The underlying processes can be regarded as physical polymerisations leading to a structural diversity, just as complex as in case of macromolecular chemistry. Several low molecular weight gelators and dyestuffs, with the cationic dyestuff pseudo-isocynanine chloride (PIC) as the most recent example, have been selected for a detailed investigation of their self-assembly with time-resolved light scattering. These systems are compared with corresponding experiments on the behaviour of Ab-amyloid responsible for the Alzheimer disease or on vimentin, an intermediary filament protein from the cytoskeleton. It is the final goal to unravel general principles of such self-assembly mechanisms which facilitates to control aggregate size and aggregate morphology and to develop synthetic systems in analogy to hierarchical structure formation in nature.

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