New Malvern application note illustrates how Viscotek SEC-MALS 20 measures protein aggregation

A new application note exploring the measurement of protein aggregation using the recently launched Viscotek SEC-MALS 20 light scattering detector is now available on the Malvern Instruments website. ‘Measuring protein aggregation with the Viscotek SEC-MALS 20’ describes the use of the new system in size exclusion chromatography (SEC) analysis of a variety of protein samples, including bovine serum albumin, thyroglobulin and pepsin. These data demonstrate the detector’s ability to simultaneously and accurately measure molecular weight for both larger (>10 - 15 nm) and smaller sized components within a mixture, an important feature for aggregation studies.  The new application note can be downloaded from the Malvern website at

Protein aggregation is recognized as a major issue in the biopharmaceutical industry. Proteins have a tendency to aggregate over time and under a variety of conditions. In clinical use as therapeutics, this presents a risk of them becoming not only ineffective but potentially immunogenic. In the highly dynamic environment of biopharmaceutical development, with its evolving regulatory concerns, many different analytical techniques are used to examine protein aggregation but SEC-MALS is already an established approach.

Data from the Viscotek SEC-MALS 20 is used in calculations of both molecular weight and radius of gyration. Light scattering detectors are valued for their ability to directly determine absolute molecular weight but this is easier for smaller molecules, which scatter light isotropically, than for larger, anisotropic scatterers. By incorporating detectors at 20 angles, including one at 90o, the Viscotek SEC-MALS 20 produces accurate data for molecules in a wide range of sizes, maximizing its value for applications where differently sized components are present.

The Viscotek SEC-MALS 20 system offers more detectors and higher accuracy than any other commercially available MALS detector. An innovative vertical flow cell with radial optics allows the use of any mobile phase without the need to alter optical properties of the detectors. Operating via Malvern’s established OmniSEC software, the Viscotek SEC-MALS 20 is available as a standalone unit, compatible with any commercially available GPC/SEC set up, or integrated within multi detection Viscotek systems. Its recent addition to Malvern’s Viscotek range means that the company now offers the most comprehensive choice of light scattering detectors for GPC/SEC analysis, including options for low angle, right angle and multi angle scattering.