Protein measurements with the Zetasizer µV

This application note describes a selection of measurements made on a GE AKTA basic system. Since the unit only contains a UV detector for measuring sample concentration, this can be used for the molecular weight calculations instead of the more commonly used refractive index detector, provided that the molar extinction coefficient of the sample protein is known. If this is not known, then reliable estimates can be made based on the amino acid sequence of the sample.

The Zetasizer μV is a dynamic and static light scattering (DLS & SLS) system capable of making measurements of molecular size and molecular weight in a batch cuvette and also when connected to a size-exclusion chromatography (SEC) system in conjunction with an OmniFACE connection box (figure 1).