I Have purified my protein with Ni NTA chromatography.In second step chromatography i have used anion exchange chromatography to remove dimer from monomer.my protein PI is 4.9.i have no problem so far.i got single band at 45 kd with respect of my protein after anion exchange chromatography.(no dimer at all,please see the attachment)

My protein elute at ~300 mM Nacl and 30 mM bis tris.2% glycerol.pH-7(AEC)and i stored my protein at -80.

my questions are

1. Is high salt concn cause problem during protein storage?

2.that dimer came back (very less as observed in sds)how can i prevent that dimer formation later during my experiment.(i used protein after thawing)

how can i overcome all these problem.we have no akta system.i did it manually.please give me suggestions.

My protein elute at ~300 mM Nacl and 30 mM bis tris.2% glycerol.pH-7(AEC)and i stored my protein at -80.

my questions are

1. Is high salt concn cause problem during protein storage?

2.that dimer came back (very less as observed in sds)how can i prevent that dimer formation later during my experiment.(i used protein after thawing)

how can i overcome all these problem.we have no akta system.i did it manually.please give me suggestions.