Protein Crystallography and
Biophysics Centre (BiophysX)
Institute of Structural and Molecular Biology
(ISMB)
Birkbeck College / University College London
Dynamic Light
Scattering (DLS) measures the
light scattered by solutions of
macromolecules, and monitors
changes in time due to
diffusion, i.e. translational
molecular movement. This gives
information on the size (radius,
not molecular weight) on a pure
preparation, and it is very good
at detecting heterogeneity,
particularly otherwise invisible
aggregates. The measurement is
quick and requires small,
recoverable volumes of sample,
and is therefore an obvious
quality control.
Sample Requirements
Volume: 5 μl for the rUNt blade cell,
12-15 μl for cuvette measurements.
Sample is recoverable. Cuvette
measurements provide more accurate
results.
Concentrations: depends on the sample
size. For proteins 1 mg/ml provides
sufficient results. If unsure use the
Concentrator Calculator in the software
(under Tools).
Negative control: ordinary buffer
solutions should not scatter light,
however a control is required if the
buffer contains large additives or
detergents.
Positive control: 1-2 mg/ml lysozyme
or BSA can be used as reference
measurements.
