Viscotek has released an application note that describes a light scattering technique that could be helpful in gel permeation chromatography (GPC) applications.
The note details how the technique could be suited to applications where the demands of sample solvent and mobile phase are different.
Solvent-enhanced light scattering (SELS) in combination with GPC allows users with two different solvents to separately optimise the sample preparation step and the chromatographic conditions to increase the dn/dc value to get better light scattering responses.
In the application note an example of a fluoropolymer analysis by SELS-GPC is shown.
Although the fluoropolymer is quite soluble in tetrahydofuran (THF) the dn/dc in this solvent is very low and the light scattering response poor.
While using a low refractive index solvent like acetone increases dn/dc the sample is not soluble in acetone.
But by dissolving the sample in THF and injecting the solution into a mobile phase of acetone (SELS concept) the researchers were able to maximise the accuracy and reliability of the GPC-LS analysis while using a cheap and safe solvent as mobile phase.
