Synthesis and Functionalization of FNA

Phosphoramidite reagents used for the synthesis of FNA were purchased from Glen Research (VA, United States): spacer 18 phosphoramidite (10–1918), DBCO-dT-CE phosphoramidite (10–1539), Thiol-Modifier C6 S-S (10–1936), biotin CPG (20–2993). N-terminus azide modified Aβ42 [K(N3)-Aβ42] peptide was purchased from GenScript Biotech (NJ, United States). N-(g-Maleimidobutyryloxysuccinimide ester) GMBS was purchased from Pierce Biotechnology (Grand Island, NY). Streptavidin was obtained from Sigma-Aldrich (MO, United States) and Tris-(2-Carboxyethyl) phosphine-HCl (TCEP-HCl) was purchased from Hampton Research Inc. (CA, United States). 1-(3-aminopropyl) silatrane (APS) was synthesized as previously described (Shlyakhtenko et al., 2013 (link)). β-mercaptoethanol, NHS-PEG₄-DBCO and all other reagents or solvents were purchased from Sigma–Aldrich (MO, United States).