Fig. 2
Effect of surface-coated gold NPs on ThT fluorescence detection of Aβ1-40 aggregates. Aβ1–40 fibrils diluted in 40 mM Tris–HCl (pH 8.0) to a final concentration of 5 μM were combined with 8.75 μM ThT and incubated (2 h) alone (control) or with 5 pM, 10 pM, 20 pM, 50 pM, 100 pM, or 200 pM NPs. a Incubation with 18 nm NPs displaying citrate (■), CTAB (●), PAA (▲), or PAH (♦) surface chemistries. b Incubation with 8 nm (▶), 18 nm (▲), or 40 nm (◀) NPs coated with PAA. ThT fluorescence was evaluated, and results are expressed as the fraction of ThT fluorescence observed for the control. Error bars represent SEM, n = 3. † p < 0.05 and *p < 0.001 vs. control