DLS, an acronym for "Dynamic Light Scattering," refers to a technique used to measure the size and motion of particles in a suspension or colloidal system based on light scattering. It is commonly employed in the field of particle and materials characterization, particularly for analyzing nanoparticles and macromolecules.
In DLS, a laser beam is directed at the suspension, and the scattered light is recorded and analyzed to determine various parameters. The technique utilizes the random Brownian motion of particles within the liquid medium to obtain information regarding their size and diffusion coefficient. By studying the fluctuations in scattered light intensity, correlations in movement can be determined, and the particle size distribution can be calculated through mathematical algorithms.
DLS provides valuable insights into particle size distributions in terms of the hydrodynamic diameter and polydispersity index. The hydrodynamic diameter accounts for the size of the particle as well as the effect of its shape and frictional properties on its motion through the liquid medium. The polydispersity index indicates the uniformity or heterogeneity of the particle size distribution, with lower values indicating a more monodisperse system.
Applications of DLS are vast and diverse, ranging from fundamental research in physics and chemistry to industrial applications in pharmaceuticals, cosmetics, and material science. It aids in the characterization of nanoparticles, polymers, proteins, liposomes, and other colloidal systems. DLS is highly valuable in assessing the stability, aggregation, and interactions of particles in suspensions, providing crucial information for numerous scientific and industrial practices.
