DLS

Dynamic Light Scattering (DLS) is an important tool for characterizing nanoparticles and other colloidal solutions.  DLS measures light scattered from a laser that passes through a colloidal solution.  By analyzing the modulation of the scattered light intensity as a function of time, information can be obtained on the size of the suspended particles.  The analysis is based on the diffusive motion of particles in solution (Brownian motion) in which larger particles will move more slowly than smaller particles.   The hydrodynamic diameter (the diameter of a hypothetical nonporous sphere that diffuses at the same rate as the particles being characterized) can be calculated from the time dependence of the scattering intensity measurements. The hydrodynamic diameter is an important complement to other sizing measurements (such as TEM) because it provides information on the aggregation state of nanoparticle solutions.  Stable unaggregated colloidal solutions will have particles with hydrodynamic diameters similar to or slightly larger than their TEM size while highly aggregated solution will have hydrodynamic diameters that are much larger than the TEM size. 

At nanoComposix, DLS measurements are performed on a Malvern Zetasizer Nano ZS instrument equipped with a HeNe laser operating at 632.8 nm and a scattering detector at 173 degrees.

To take advantage of our DLS Service please contact us at service@nanocomposix.com.  A nanoComposix representative will contact you within 1 business day to discuss your needs, provide suggestions, and answer your questions.