Fluorescence Spectroscopy as a Tool to Characterize Amyloid Oligomers and Fibrils

Amyloid fibrils as dispersing agents for oligothiophenes: control of photophysical properties through nanoscale templating and flow induced fibril alignment

“…Amyloid brils or amyloid plaques, are intensively studied due to their association with a variety of disease states, 12 and the use of uorescent probes is an attractive way of detecting such species. 30 To be of relevance for amyloid detection, optical probes must be water-soluble. However, this means that such probes will bind to amyloid materials in an equilibrium process.…”

“…Such processes forms the basis for amyloid detection by various dyes such as Thioavin T, 27 Congo red, 28 and watersoluble oligothiophenes. 29,30 All these dyes share the common feature of having a thin and at linear chain of aromatic hydrocarbons; a type of structure that has been shown to have high affinity for structural elements, in particular b-sheets, within the amyloid materials. The amyloid structure can thus be viewed as being a structural framework suitable for biomolecular organization of linear p-conjugated molecules.…”

“…Moreover, the effect of connement of 6T into carbon nanotubes has been studied. 38,39 Due to the proven capability of amyloid materials to host amphiphilic linear p-conjugated organic molecules [27][28][29][30] amyloid brils should be able to act as efficient dispersing agents for materials such as oligothiophenes. Moreover, the ne structure present in amyloid brils might enable orientational ordering of linear aromatic molecules such as 6T with nm precision.…”

Two-Photon Fluorescence and Magnetic Resonance Specific Imaging of Aβ Amyloid Using Hybrid Nano-GdF3 Contrast Media

“…Among possible imaging technologies, fluorescence appears as a tool of choice for its high sensitivity and resolution. Several fluorescent probes have been used in vivo via multiphoton microscopy in animal models . For AD, such fluorescent probes are useful as research tools but with strong potential for future applications. ,, Luminescent conjugated oligomers, LCOs, are interesting due to their specific spectroscopic response which is typical of their conformation, and they reliably report on amyloid fibrillation, providing unprecedented contrast and new insight into the time-changes of plaque inhomogeneity. − This optical feature of the LCO depends on the conformational variations in protein aggregates ,,, and is not observed with the usual amyloidotropic dyes .…”

Binding of Polythiophenes to Amyloids: Structural Mapping of the Pharmacophore

“…The binding affinity of marker molecules depends critically on the pharmacophore presented by the amyloid, in particular the surface geometry and the distribution of charges. While the rigid β-sheet part of the amyloid structure remains largely unaffected by the interaction, the conformation of the marker changes, leading to a readout in its optical properties like fluorescence wavelength or birefringence …”