I work with AAV and am looking to improve AAV purification as well as induce enrichment of full capsids and reduction of empty capsids. One approach listed in literature is to remove divalent ions from solution which are important in stabilizing empty capsids. This will theoretically damage them and lead to better separation of full and empty capsids.

What is your experience with using chelators like EDTA/EGTA with affinity chromatography? I want to use them in the wash steps of affinity capture chromatography to remove divalent ions like Ca++ from the column. Would this affect affinity chromatography in any way? I am aware that i have to wash the chelators off the column before elution because they would interfere with any subsequent anion exchange steps. Any thoughts?