Bio-Rad Model 111 Mini IEF Cell - Manual (Page 11)

Note: The selection of appropriate ampholyte is determined by the pH range required for a
particular separation. Bio-Lyte ampholytes are specifically blended to produce a linear
gradient within the stated range and no further blending is generally needed. Particular
separations, however, may require a combination of two or more ampholytes to achieve a
desired result.
3.4 Use of Gel Support Film for Polyacrylamide
1. Remove a sheet(s) of Gel Support Film for Polyacrylamide (catalog number 170-2983) from
the package, and then reseal the package. Polyacrylamide gel support film is sensitive to light
over prolonged periods and must be kept sealed in the package until use. After the gel has
adhered to the support film, the film is no longer light sensitive.
2. Polyacrylamide gel support film has two surfaces, a treated (hydrophilic) side which the
acrylamide adheres to, and a hydrophobic surface. The sheets are packed with printed
interleaf paper which protects the treated surface. All sheets are packed treated side up. A
drop of water will bead on the hydrophobic surface and spread on the hydrophilic surface.
3. Pipet a few drops of water onto the clean glass plate.
4. Place the hydrophobic side of the gel support film against the plate.
5. Roll the gel support film flat with a test tube or similar object to force out excess water and air
bubbles.
6. Carefully wipe or blot off any excess liquid at the edges. The gel support film is now ready for
use, and should be used as soon as possible.
Note: Basic ampholytes (pH > 8.0) have been found to interfere with gel adhesion to the
polyacrylamide support film. Increasing the concentration of ammonium persulfate to 0.7
mg/ml in the final acrylamide gel solution (add 70 µl of 10% ammonium persulfate per 10 ml
solution) should alleviate the problem. Adhesion may also be affected by prolonged soaking
in acid solutions, such as in staining and destaining. Do not soak longer than absolutely
necessary to achieve the desired result.
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