Figure 3.

Fluorescence staining of Aβ42 oligomers. (A)–(E) show the c(s) distributions based on fluorescence measurements for 40 μM Aβ42 in the presence of different fluorescent dyes, SO (orange), hFTAA (dark red), SG (green), YOYO (red), and DCVJ (cyan). In each case, the c(s) distribution of a separate absorbance measurement (black) without dye was added as a reference. (F) shows the superposition of all curves. All samples were measured in 20 mM sodium phosphate buffer (pH 7.4) with 25 mM NaCl (2% dimethyl sulfoxide for samples with fluorescence dyes) at 20°C and 60,000 Rpm. The incubation time before analysis was 6 h. Magnifications visualize oligomeric species from 1 to 19 S. The c(s) distributions were normalized to one according to the area under the curve for the complete s-value range from 0 to maximum s-value. To see this figure in color, go online.