Bio-Rad Media Sampler Pack - Manual (Page 8)

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Section 4. Cleaning-in-Place and
Regeneration
CFT should be regenerated at the completion of each run with 3–5 CV of
400–500 mM potassium or sodium phosphate buffer (pH 6.8). Remove more
tightly bound and basic proteins (pl > 7) with 3–5 CV of 1–2 M KCl or NaCl, or
400 mM trisodium phosphate (pH 11–12). Rinse the column with 1 CV of H
2
O
between any change of salt to avoid precipitation.
Urea (8 M) and guanidine-HCl (6 M) are effective cleaning agents (see Chemical
Compatibility above).
Pure organic solvents or different percentage alcohol solutions in water may be
used to clean CFT. Since the viscosity of alcohol-water solutions is greater than
that of water, lower the flow rate when changing from aqueous to organic solvent
solutions. Before cleaning with 70–100% ethanol, methanol, isopropyl alcohol, or
acetonitrile, rinse the column with 1 CV of distilled water to avoid salt precipitation.
After cleaning with the organic solvent, rinse with 1 CV of water followed by 1 CV of
5 mM sodium or potassium phosphate buffer (pH 6.8).
Section 5. Sanitization
CFT should always be sanitized prior to storage to avoid growth of
microorganisms. Such contamination can lead to localized production of acid,
resulting in damage to the support. CFT is stable in 2 M potassium or sodium
hydroxide. To sanitize, first regenerate the column with 400–500 mM phosphate
buffer as mentioned above. Then rinse the column with 3–5 CV (1 hr exposure) of
1–2 M potassium or sodium hydroxide.
When reequilibrating from strong hydroxide solutions, rinse with 400–500 mM
potassium or sodium phosphate buffer at the desired pH until the pH of the eluent
is equal to the pH of the applied buffer (approximately 3–5 CV).
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