Hydrodynamic diameter and Particle Size
Hydrodynamic diameter and Particle Size by Dr. Mirza Salman Baig The Hydrodynamic diameter (d H ) or the hydrodynamic particle size or is defined as the size of a hypothetical spherical particle that diffuse at the same speed as the actual particle being measured using dynamic light scattering (DLS) or Particle tracking analysis (PTA). The particle size is determined using Stokes-Einstein equation. The nanoparticle consists of the particle core along with layer of ion or polymers bound to its surface. The d H is a very useful parameter for characterizing particles size when in solution and includes coatings or surface functionalization on the particle being investigated. Figure depicting hydrodynamic diameter and core diameter of a particle Diffusion rate of particles are measured using DLS or PTA method. In a DLS method the colloidal suspension of particles is bombarded with laser light (Gittings & Saville, 1998) (Gordillo-Galeano & Mo...