Bio-Rad Profinity IMAC Resins - Manual (Page 14)

For all buffer formulations add water to 1 L, adjust
pH to 8.0 with KOH or H
3
PO
4
, and filter through a
0.2 µM filter.
Native buffers can be stored up to 1 year at
4–22°C; denaturing buffers must be made fresh
and used within 7 days, or frozen in aliquots at
–20°C for later use.
Section 6
Quick Solubility Screening
Protocols
Before choosing a native or denaturing purification
protocol, it is useful to determine the approximate
expression level of a protein, and to determine if the
overexpressed target protein partitions into the
soluble or insoluble fraction. Soluble proteins are
typically purified with the native purification procedure,
while insoluble proteins must be solubilized in
stringent denaturants (urea or guanidine) and are
purified with the denaturing procedure.
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