Problems with immobilisation

Hi Claude,

Looks ok. The activation is what can be expected.
The immobilization of the ligand looks a little strange. The jump at the beginning is unexpected. I wonder how concentrated is the stock solution of the ligand and what is the buffer composition?
The amount of bound ligand seems ok (~ 8000 RU?).

If the deactivation in detrimental for your ligand you can only check with a positive interaction. For instance with an antibody?
If you think that the deactivation solution is to harsh, use a diluted solution or use just TBS. I think that you do not have to worry if the deactivation is efficient enough. Seven minutes is.

At this point, try you analyte. The easiest method is to use the kinetic titrtion method. See www.sprpages.nl/component/content/articl...netic-titration.html
(It is a direct link, not in the regular sprpages )

regards

Arnoud

In which buffer was the protein diluted? Could be that the immobilization pH is to low and the protein is aggregated? I also agrre that the Rim 3500 is ok if you don't have really small analytes.
eya

I used Sodium Acetate pH 5.2 for that run. I am currently using Molecular Grade H2O and getting decent results with immobilizing the protein.

Claude