Fig. 4
Characteristic filling times of the nanopores. Characteristic times of the nanopore filling by capillarity (blue dotted line, ti) and particle diffusion (red dashed line, tD) varying the thickness of the nanoporous silica tablet (nanopores with 11.04-nm diameter; solution of 1AKI proteins in water at 1% weight fraction). The particle diffusion process through the fully hydrated pores requires a characteristic time tD two orders of magnitude higher than ti, in all the analyzed configurations. The inset shows the ratio between the particle concentration at the center of the nanopore (ci,c, at x=T/2) and the bulk one (ci,b, at x=0 and T) as a function of time for different thickness (T) of the tablets