GE PhastSystem User Manual page 93

Symptoms
PhastGel IEF media
Dark area across the
gel
Dark background
Dark, uneven back-
ground staining
Probably Cause
No (or too little) copper sulphate in
the staining solution.
Old fix and wash solutions.
1. Old fix and wash solutions (the
first two solutions). This is usually
visible only after the gel is dry.
2. The coomassie concentration is
too high.
Trouble Shooting Guide
Solution(s)
Add enough CuSO to make the
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solution 0.1% CuSo .
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Do not recycle the fix and wash
solutions more than 3 or 4 times.
The gels can be further destained
even after drying. Place the gels in
the development chamber and start
the destaining step.
1. Recycle the fix and wash solu-
tions no more than 3 or 4 times.
Destain the gel again.
2. Check the concentration for the
technique you are using (0.02%
for IEF).
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