Hi all
I am doing an experiment whereby I extract IgG from serum using an affinity collumn assay (Protein A- columns: NAb Spin Columns, Thermo Scientific) , and I want to expose cultured endothelial cells to the negative fraction of serum (IgG-depleted serum).
However, per protocol the serum has to be diluted (1:4) before passing through the Protein A- columns (NAb Spin Columns, Thermo Scientific), and the effect I am looking for is lost when cells are exposed to the diluted serum.
So two choices:
a) I try to pass undiluted serum through the columns
b) I try to "re-concentrate" the negative fraction through dialysis with a concentrating gradient (such as Spectra/Gel Absorbent with FLoat-a-Lyzer G2, Spectrum Labs).
Do you have any experience with any one of these alternatives?
Best,