Solvent Enhanced Light Scattering of Fluoro-Polyester
Traditionally in GPC, the sample dissolution solvent and the mobile phase are one and the same. However, a closer look at the demands of sample solvent and mobile phase suggests that this should not always be the case.
sponsored by Malvern Panalytical
Introduction
Viscotek is a strong advocate of good chromatography as a prerequisite for GPC (Gel Permeation Chromatography) data accuracy. Our recent work in application development has been driven by extremely difficult samples from industrial, biopharmaceutical and academic sources. These samples present challenges such as sample solubility, column adsorption as well as detection issues. This report will attempt to highlight a new approach that will be very helpful in certain advanced GPC applications.
Reasons for SELS
Traditionally in GPC, the sample dissolution solvent and the mobile phase are one and the same. However, a closer look at the demands of sample solvent and mobile phase suggests that this should not always be the case. For the sample solvent, one simply wants a solvent that quickly and completely dissolves the sample. Cost and chemical structure are secondary issues. For the mobile phase the requirements are significantly different:
- Because of the high consumption, material cost is a significant factor.
- The dn/dc of the sample in the mobile phase should be as high as possible so that the RI and, especially, the light scattering detector sensitivities are enhanced. In most cases mobile phases with low values of RI will be best.
- The mobile phase does not have to dissolve the sample; only support (or maintain) its solubility during the analysis.
