PaD213-A5 discriminates between different Aβ42 fibrils. A, titration ELISA of PaD213-A5 on different kinds of Aβ42 fibrils. Plates were coated with 100 ng of Aβ42 fibrils from 100 mM Na-Borate, pH 8.6 (solid line) or 10 mM Tris–HCl, pH 7.4 (dotted line). Bound ScFv-Fc antibodies were detected using a peroxidase-labeled goat anti-human antibody recognizing the Fc fragment (1:35,000). Right: representative TEM images of Aβ42 fibrils obtained from monomers purified in (B) 100 mM Na-Borate, pH 8.6 or (C) 10 mM Tris–HCl, pH 7.4, the scale bar corresponds to 200 nm.