Malvern Instruments has made available a downloadable presentation that considers the real accuracy and reproducibility of dynamic light scattering and the relevance for users' applications.
The presentation is presented by Dr Ulf Nobbmann, a specialist in biophysical characterisation.
Dynamic light scattering (DLS) is used in the size characterisation of proteins, polymers and colloidal dispersions, and the methodologies outlined by Nobbmann allow researchers to assess the validity, accuracy and precision of the technique for their specific applications.
The effective application of DLS relies on the three Rs of repeatability, reproducibility and robustness.
In his presentation, Nobbmann shows how a practical repeatability of better than one per cent is achievable.
Details of how to account for the effects of particle size mixtures, scattering angles and ways of testing repeatability are all covered.
Most applications of DLS are in the nanometre to sub-micron size range.
At the low size extreme, low scattering intensities can lead to more error, while at the high size extreme, number fluctuations or sedimentation can increase uncertainty.
It is therefore good practice to assess repeatability of results.
The Malvern Instrument presentation explains what to watch out for when assessing the measurement of real samples for real applications and provides potential solutions for some of the most common causes of error.
