Labconco Gel Dryer 4330150 - Manual (Page 15)

NORMAL OPERATION
15
Gel Drying
1. Turn on the heater timer and select a heater temperature. The temperature should
match the gel and its intended use. For polyacrylamide gels, 80°C is used for most
applications. Some scintilants for fluorography are heat sensitive and a lower
temperature (60°C) should be selected. If agarose gels are to be dried, they will melt
rather than dry at high temperature, so a setting of 40°C should be used. When most
of the water has been removed from the gel (reduced thickness), the temperature may
be safely raised to finish the drying process.
2. The time necessary for drying is a function of the gel type, thickness, solvent (e.g.,
50% methanol for fixed gels), dryer temperature and vacuum efficiency. Typically,
10% acrylamide gels in 50% methanol 10% acetic acid will dry in about 1 hour at
80°C. Generally, the gel is dry when the surface temperature over the gel is the same
as the surrounding area. When dry, the contour of the gel seen through the rubber
sheet will disappear.
3. If the vacuum seal is broken before the gel is dried, the gel will shatter and be lost. If
in doubt, it is best to let the gel dry for a longer period of time. Cracking of
polyacrylamide gels may be reduced by soaking the gel for an hour in 5% glycerol
prior to drying. This adds flexibility to the dried product as well. Gel cracking may
also be avoided by allowing the gel to cool under vacuum. We recommend setting the
vacuum timer for about 30 minutes longer than the heater. After drying, peel off the
Mylar or polyethylene sheet (or Saran Wrap if used) and remove the gel from the
dryer. The gel can now be kept as a permanent record or be auto-radiographed.