Bio-Rad Silver Stains - Manual (Page 13)

Problem Cause Solution
Background dark or uneven (cont.) Contaminants in water. Prepare all solutions with
double-distilled water with
a resistance of at least
18 M
Ω-cm.
Low protein staining sensitivity or Excessive silver ions washed out Verify that each post-
no staining of gel. staining water wash is
exactly 1 min long.
pH of developing working Verify the working solution
solution too low. pH = 11.6 ± 0.5, and
prepare new developing
solution with development
buffer concentrate, if
necessary.
Reducer not present in Prepare new developing
developing working solution. solution with image
developer concentrate.
Insufficient fixing due to variable Extend the time of the
fixing characteristics of different fixing step.
proteins.
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