Bio-Rad PROTEAN® IEF Cell Accessories - Manual (Page 10)

Figure 8. Loading sample into cup with pipet.
Optional: The integrity of the seal between the gel surface and the cup can be verified by
adding some rehydration buffer to the cup prior to loading the sample. When a leak proof seal
is confirmed, carefully remove the rehydration buffer and replace with the sample.
4. Overlay each sample cup with mineral oil to prevent evaporation.
5. Completely overlay each strip with mineral oil.
6. Carefully place the focusing tray with the properly positioned electrodes and sample cups on
the temperature-controlling platform of the PROTEAN IEF cell.
Figure 9. Insertion of Focusing tray into PROTEAN IEF cell.
2.6 Focusing Conditions
Focusing conditions will vary with sample composition, sample complexity, IPG pH range and
strip length. The following parameters are recommended guidelines. We recommend maintaining
a current limit of 50 µA per strip to minimize excessive heat generation and subsequent increase
in the possibility of burned regions in the IPG strips.
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