Figure 3.

Diffusion coefficient D of Hb in RBCs as a function of temperature. The diffusion coefficients were measured with QENS on IRIS (circles), on IN16 (diamonds), on IN10 (squares) and with neutron spin-echo spectroscopy on IN15 (triangle) [14]. D₀ was measured with dynamic light scattering and scaled data points are given as small empty circles. The thin dotted and the thin dashed line show the theoretical values of short-time and long-time self-diffusion of Hb at a volume fraction of ϕ = 0.25 with hydrodynamic interactions () [47]. The thick dotted and the thick dashed line represent the theoretical values for short-time and long-time self-diffusion of Hb assuming that a hydration layer of 0.23 gram H₂O per gram protein is bound to the surface of Hb. Experimental data agree well with the theoretical considerations when the bound hydration water layer is taken into account () [47].