Figure 4.
The mobility of trapped particles can be restored via charge screening. (a) Schematic illustration of charge screening as induced by ions (orange cloud) that are added to the vitreous. Charged particles (or polymers of the vitreous) concentrate counterions around their surface and thus avoid electrostatic trapping. (b) When KCl or NaCl is injected together with the particles, the mobile fraction of amine-terminated (NH2) 200 nm polystyrene particles in ovine vitreous humor is increased compared to physiological salt concentrations (154 mM). At 2 h after injection, this remobilization effect is not present any more. More than 1000 particle trajectories were analyzed per experimental condition and categorized into mobile and immobile particle fractions. The error bars denote the standard deviation for those fractions as obtained from at least three vitreous samples. Asterisks denote statistically significant differences compared to physiological salt conditions (∗∗∗p < 0.001). To see this figure in color, go online.