Absolute molar mass and size

Not all macromolecules behave alike. Your samples may have a different conformation than molecular standards or exhibit unexpected column interactions. As an absolute technique for determining molar mass and size in solution, SEC-MALS - the combination of size-exclusion chromatography with multi-angle light scattering – offers an advanced characterization technique and overcomes the many limitations of column calibration.

Even though Peak 1 elutes earliest, MALS shows that it does not have the highest molar mass for this example of protein aggregates and fragments.

One small step for SEC, one giant leap for your lab

If you already analyze your samples by analytical SEC, you have probably overcome the most challenging part of SEC-MALS: finding the right column, mobile phase and other conditions that ensure good separation and recovery. Now you are ready to add MALS for absolute characterization and deeper understanding.

As shown in the example on the right, getting the correct molar mass with MALS is independent of molecular conformation and elution volume.