Labeling Procedure1. Dialyze the protein solution in conjugation buffer (10-20 mM MOPS, 0.2 M NaCl, 2 mM EDTA, 5% glycerol, pH 8.0) at 4ºC overnight.2. After dialysis, adjust the protein concentration to 15-30 mM.3. Add 15 ml of 20 mM FeBABE DMSO solution to 1 ml of the protein solution and incubate it at 37ºC for 1 hour. The final concentration of FeBABE is 0.3 mM (10-20X excess to the protein).4. Dialyze the reaction mixture in protein storage buffer (10-20 mM Tris, 0.1-0.2 M KCl, 10 mM MgCl2, 0.1 mM EDTA, 50% glycerol, pH 7.6) at 4ºC overnight.
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