GE PhastSystem User Manual page 86

Trouble Shooting Guide
Symptom
Wavy bands
Local band
disturbance
Wavy bands at or
near the point of
sample application
Dotted or slashed
bands
2
Probable Cause
Dirty electrodes
Air bubbles present between the gel
and the bed.
Too much salt in the sample.
1. Field strength too high for sample
application.
2. Air bubbles in the sample.
Solution(s)
Clean the electrodes with a wet, lint-
free cloth after every run.
From time to time, pull out the
electrode assembly and wash the
electrode with detergent or HNO
using a soft brush. Rinse thoroughly
with distilled water. Airdry or dry
with a hair dryer.
Use about 60-75 µl of water to posi-
tion the gels on the bed. Remove all
air bubbles between the gel and the
bed.
Dilute or desalt the sample. For IEF,
try another sample application
position.
1. Decrease the field strength for the
sample application step e.g. use
220 V, 2.5 mA for IEF, and 400 V,
1.0 mA for native-PAGE.
2. Make sure the sample does not
contain air bubbles.
3