Table 1.

Comparison of rates in aqueous buffer and 6 M GdmCl

	kobs (μs−1)		$\frac{k_{\text{obs}}\left(\text{buffer}\right)}{k_{obs}\left(\text{GdmCl}\right)}$	kR (μs−1)		$\frac{k_{\text{R}}\left(\text{buffer}\right)}{k_{\text{R}}\left(\text{GdmCl}\right)}$	ηkD (cP μs−1)		$\frac{\eta k_{\text{D}}\left(\text{buffer}\right)}{\eta k_{\text{D}}\left(\text{GdmCl}\right)}$
Peptide	Buffer	6 M GdmCl		Buffer	6 M GdmCl		Buffer	6 M GdmCl
cc-AGQ9	2.0 ± 0.2	0.21 ± 0.02	9.5 ± 1.7	2.4 ± 0.2	0.35 ± 0.03	6.9 ± 1.2	6.4 ± 1.2	0.94 ± 0.17	6.8 ± 2.6
hIAPP	0.93 ± 0.07	0.23 ± 0.02	4.0 ± 0.7	1.2 ± 0.1	0.32 ± 0.03	3.8 ± 0.7	3.6 ± 0.6	1.3 ± 0.2	2.8 ± 1.1
rIAPP	0.64 ± 0.05	0.13 ± 0.01	4.9 ± 0.9	0.89 ± 0.07	0.19 ± 0.02	4.7 ± 0.8	2.0 ± 0.4	0.62 ± 0.11	3.2 ± 1.2

Uncertainty in k_obs (∼9%) was estimated by calculating the standard deviation of log k_obs values obtained from independent fits of the relaxation rates relative to the best-fit estimates obtained from the global fits of viscosity dependence at all temperatures. The number of degrees of freedom was (N – 2) × (number of temperature values – 1), where N is the total number of points. The errors for k_R were assumed to be the same as for k_obs (∼9%) and the error on ηk_D was estimated from the error on the slope of a straight line passing through two values of k_obs (by simple error propagation: δk_D/k_D = 2 × δ k_obs/Δ k_obs = 18%). The errors on the ratios obtained by error propagation are ∼13% for k_R/k_R and ∼26% for ηk_D/ηk_D.