Measuring protein molecular weight using the Viscotek SEC-MALS 20 connected to a Waters Empower® SEC system
Application Note Dec 12, 2014
Malvern Instruments Limited
Biopharmaceuticals are drugs made from biological molecules such as proteins. Protein activity is often defined by its molecular weight and aggregation state. Light scattering is more and more commonly being used to measure the molecular weight of proteins, their oligomers and their aggregates. SEC-MALS is one of the more common implementations of light scattering for protein measurements. Malvern’s Viscotek SEC-MALS 20 is a multi-angle light scattering instrument with 20 detection angles for the measurement of protein absolute molecular weight and oligomeric state. It can also be used to study the molecular weight and size of protein aggregates, as well as for the analysis of synthetic and natural polymers. The Waters Alliance® system is frequently used in protein separations and is popular throughout the biopharmaceutical environment, particularly due to its powerful software, Waters Empower®. Adding advanced detectors to most SEC systems is usually possible thanks to the generic analog and digital connections that can be used to transfer signals between devices but software packages are often incompatible. In this application note, we show that Malvern’s OmniSEC software can now communicate with Waters Empower® for the seamless exchange of sample sequences. This allows OmniSEC to follow the injections performed by a Waters SEC system and to synchronize data collection. A selection of proteins was used to demonstrate the measurement of protein molecular weight, oligomeric and aggregation state.