Bio-Rad Profinity IMAC Resins - Manual (Page 29)

Problem Possible Cause Solution
Precipitation during Binding capacity of Load less sample
purification cartridge exceeded
Protein aggregating Include low levels of
detergent (0.1% Triton
X-100, Tween 20) in
purification. Include glycerol
up to 10%
Protein too concen- Elute with imidazole gradient
trated during elution (10–250 mM) rather than step
elution
Eluted protein is Contaminants co-eluting Elute with imidazole gradient
impure (10–250 mM) rather than step
elution
Contaminants co-eluting Increase the imidazole in the
wash but keep below 40 mM
to increase wash stringency
Target protein is Proteolysis of target Add protease inhibitors to
degraded protein lysate. Purify at 4°C or under
denaturing conditions
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