cytiva Ettan IPGphor Cup Loading Manifold User Manual page 25

Symptom
Sample leaks from cup
Ettan IPGphor User Manual 11003460 AE
Possible cause
Conductivity/ionic
strength is too high.
Incorrect cup placement.
5 Troubleshooting
Remedy
Check that the actual
number of Immobiline
DryStrip gels on the Ettan
IPGphor platform is the
same as the number of
gels entered in the
protocol.
Prepare the sample to
yield a salt concentration
less than 10 mM. The
recommended IPG Buffer
concentration is 0.5%. A
maximum of 2% is advis-
able only if sample solu-
bility is a problem. High
conductivity can also
arise from the use of poor
quality urea or other
denaturants. Urea is also
prone to decompose to
charged breakdown
products. Salts and ionic
impurities in the sample
can raise the conduc-
tivity of the strip.
Shorter length IPG strips
(e.g. 7 cm strips) will not
reach 8000 V. The
distance between the
electrodes is shorter so
that the voltage gradient
(V/cm) required to reach
the 50 μA current limit is
reached at a lower overall
voltage.
Check that the feet of the
cups are resting on the
bottom of the manifold
channel.
Check for correct posi-
tioning of sample cup
arms.
25