Salt required in SEC?
Posted: Thu Jan 16, 2014 10:45 pm
by separation
Am trying to eliminate the use of NaCl in SEC. If the solvent is adequently buffered (>100mM NaPO4), does the gel require such high levels of NaCl (>100mM) for stability, swelling, etc for the proteins to resolve?
Thanks
Re: Salt required in SEC?
Posted: Thu Jan 16, 2014 11:49 pm
by tom jupille
Depends on the "gel". Many polymer-based packings will shrink/swell significantly with changes in ionic strength. Some polymer-based and most silica-based packings (designed for HPLC use) have sufficient structural rigidity that salt is not required for that purpose. It may still be necessary to mitigate secondary interactions (ion exchange / ion exclusion).
Check with the stationary phase manufacturer for their specific recommendations for a particular material.