Libraries of SELEX against a-synuclein fibrillar polymorphs

We used two distinct de novo generated a-syn fibrillar polymorphs termed “Fibrils” and “Ribbons”, or F-type and R-type, respectively, to select conformational aptamers. These fibrillar polymorphs exhibit distinct structures, nanomechanical properties, shapes in the electron microscope and surfaces exposed to the solvent. Two SELEX strategies were used in parallel to isolate aptamers able to bind specifically to F-type a-syn fibrillar polymorphs. The first (SELEX S1) used counter-selection against the selection support (Bio-gel P 6), whereas the second (SELEX S2) used a more stringent counter-selection against the selection support as well as the R-type a-syn fibrillar polymorphs and the monomeric form of the protein.