Figure 3
From: Dynamics of the formation of a hydrogel by a pathogenic amyloid peptide: islet amyloid polypeptide
IAPP is surface active and forms a hydrogel at the AWI.
(a) Dynamic measurement of the surface tension for 4 μM IAPP (black line) and for DMSO in water (the same amount as in the 4 μM IAPP)(black dotted line) was monitored over time (4 point moving averages of the raw data, left panel), with the surface tension of 4 μM IAPP at the start of the reaction and at 550 sec, the rate of decrease in surface tension and the time required for this decrease (‘delay’) depicted (right panel). a.u.: arbitrary units. The mean of at least three independent assays is shown. Error bars represent ± SEM. (b) Interfacial rheological properties of a 4 μM IAPP solution were assessed at 25 °C with a controlled displacement of 5 × 10−3 rads and a frequency of 0.5 Hz. (left panel) Dynamic interfacial moduli G’ and G” as a function of time, with the inset showing a DMSO control. (right panel) G’ and G” as a function of angular frequency ω. Inset shows G’ and G” as a function of oscillation displacement.
