Dr. Fröse Software Solutions

Last Change: 29.7.2010

Why Static Light Scattering?

Static light scattering (SLS) is the only method that provides you with informations on the size and the molar mass of your sample. A sample is illuminated with a light beam and the scattered intensity is measured for various angles. The light is scattered with respect to two basic principles, which can be explained by the interferences of partial beams, that are scattered on the multiple scattering centers in the macromolecule. The mass and the size are calculated due to these two principles.

The Principles of SLS

• As more mass the particles have, as more light is scattered
• As bigger the particles are, as more light is scattered in forward direction

Using a setup that allows determining the scattered intensity for different angles, you can calculate the informations of mass and size using well known mathematical algorithms. The analysis range is 10 nm to 1 µm for the size and 1x10³ Da to 1x10⁹ Da for the masses and covers the complete RDG-Range.

If there are different particles in your sample cell, you will measure the average using SLS. To overcome this problem, combine your detection system with a chromatographic system as GPC or FFF. Now you can separate your sample with respect to the distributions and the size. In contrast to classical GPC, this method allows a absolute determination of mass and size with no assumptions on the shape or the density                                                         .

The Cerberus detector was developed as a flow detector with the goals to combine highest sensitivity with large angular range to cover a broad range of applications.