Advancements of the sFIDA method for oligomer-based diagnostics of neurodegenerative diseases

Early diagnosis of Alzheimer's disease (AD) is of great importance for the development of therapeutics and their application in the clinical environment. Amyloid beta (A beta) oligomers are crucial for the onset and progression of AD and represent a popular drug target, being presumably the most direct bio-marker. Efforts to measure A beta oligomers in body fluids are hampered by the low analyte concentration and presence of A beta monomers. The surface-based fluorescence intensity distribution analysis (sFIDA) features both highly specific and sensitive oligomer quantitation as well as total insensitivity towards monomers. In this Review, we highlight structural features of oligomeric and fibrillar A beta. Recent advancements in sFIDA assay development have been the successful automation, adaption for additional biomarkers such as alpha-synuclein oligomers, and significant improvement of essential assay parameters.