• The diameter that is measured in DLS is a value that refers to how a particle diffuses within a fluid so it is referred to as a hydrodynamic diameter

• The diameter that is obtained by this technique is the diameter of a sphere that has the same translational diffusion coefficient as the particle

• The translational diffusion coefficient will depend not only on the size of the particle “core”, but also on any surface structure, as well as the concentration and type of ions in the medium