Figure 5. Aggregates of tau incubated in 0.1% formaldehyde for 15 days.

The experimental conditions were described in Figure 3, except that the incubation time was prolonged to 15 days. A typical AFM image of tau in the presence of formaldehyde is present in A (Bar: 100 nm), together with a three dimensional image (B) for a better visual effect. Frequency counts of horizontal diameters of particles are presented in C.