Is it necessary to regenerate the column each time? March 10, 2021 05:34 No. You can regenerate the column every 3-5 times. Related articles Which endotoxin detection method should I choose? The manual mentions that the Lysis Equilibration Buffer, Wash Buffer and Elution buffer contain 50 mM NaH2PO4 and 300 mM NaCl. Is it possible to use 50mM PBS instead of them? Do you know if the cell line will remain stable in absence of hygromycin? How do I convert EU/ml to ng/ml of endotoxin? What concentration of PMSF is needed for cell lysis and protein purification?