title: Ion-specific effects modulate the diffusive mobility of colloids in an extracellular matrix gel.
abstract: The diffusion of colloids in complex biological hydrogels is regulated by a broad range of factors including geometric constraints and different types of physical interactions between the particles and the hydrogel constituents. As a consequence, the particle mobility depends not only on the hydrogel microarchitecture but also on the detailed chemical composition of the hydrogel solvent. Here, we employ single particle tracking techniques to quantify the diffusion behavior of submicrometer-sized particles in such a biological hydrogel. We observe three states of colloid mobility: free diffusion, tightly and weakly bound particles, and transitions between those states. Finally, by comparing the efficiency of particle trapping in Matrigel as a function of the ionic strength of the hydrogel buffer, we show that ion-specific effects regulate the efficiency of this trapping process.
authors: Zentralinstitut für Medizintechnik, Technische Universität München , Boltzmannstrasse 11, 85748 Garching, Germany.
authors: Fabienna
authors: F
authors: Arends
authors: Regina
authors: R
authors: Baumgärtel
authors: Oliver
authors: O
authors: Lieleg
mesh_terms: D003102:Colloids; D004058:Diffusion; D005109:Extracellular Matrix / Q000378:metabolism*; D020100:Hydrogels / Q000737:chemistry / Q000378:metabolism*; D009994:Osmolar Concentration; D010539:Permeability; D013997:Time Factors
chemical_list: D003102:Colloids; D020100:Hydrogels