I would like to perform a modified co-immunoprecipitation assay using a GFP-tagged protein. We are going to bind the tagged protein to anti-GFP antibody then bind that to protein A/G beads, however we want to be able to selectively elute the tagged protein off the beads. I know that you can elute a FLAG tagged protein off of M2 anti-FLAG antibody by adding excess FLAG, so can I use the same approach with my GFP tag? If so, does anyone know a commercially available GFP monoclonal antibody who's epitope has been mapped so I can use excess epitope to elute my protein? Or possibly a source of recombinant GFP?
I found a paper that describes a method to purify GFP fusion proteins using affinity chromatography: "Purification of GFP fusion proteins with high purity and yield by monoclonal antibody-coupled affinity column chromatography" (1). Unfortunately I don't have access to the full text, so I can't check how exactly they elute the GFP fusion protein from the column. They describe a specific monoclonal antibody they use, there should be information on how to obtain it in the paper.