Biochemistry 2280A Lecture : Types of Column Chromatography
Document Summary
Gel filtration - if a protein is small it will get stuck in the holes and stick to the hole. If they are larger they will run through the column and they will come out earlier. The smaller proteins get held up in the beads and come out later. Ion exchange - bead is charged either plus or minus and the proteins will stick based on their charge. Results in a positively charged bead (cellulose) all the beads would have a positive charge because of the cellulose. So this would bind to negative proteins to get the protein off you put in more negative ions that bump it off the beads. Beads are positively charged and have attracted negatively charged ions. Add the protein comes down negatively charged and it binds to the bead. Bring multiple negatively charged ions and bump it off.