Bio-Rad EXQuest Spot Cutter - Manual (Page 34)

4.0 GEL AND BLOT PREPARATION
Gel and blot preparation is an important part of setting up a successful cut run. Failure to prepare gels and
blots properly may result in loss of accuracy and/or decreased cutting efficiency. Gel and blot preparation is
described in Section 4.1, free gels; Section 4.2, plastic and glass-backed gels; and Section 4.2, blots.
4.1 FREE GELS
1. Store gels in a container that keeps them protected and hydrated until needed for spot cutting.
Before a gel is cut, it is best to equilibrate it in water for at least 1–2 hours or preferably overnight
and then to bring it to room temperature. This will greatly reduce any swelling that may occur when
the gel is hydrated on the gel tray.
2. Remove the gel tray from the spot cutter, place a cutting sheet on it, and then transfer the gel onto
the cutting sheet. Alternatively, use the cutting sheet to lift the gel out of its storage container and
then place both the cutting sheet and gel on the gel tray. A cutting sheet should always be used to
cover and protect the gel tray from being scored by the cutting tip. Do not remove the thin plastic film
from the cutting sheet as it is required for high cutting efficiency.
3. Position the gel(s) in the center of the tray.
4. Clamp the gels and cutting mat in place with the gel clamps (see Figure 4-1). Use two clamps to
hold a single gel in place or 2 to 4 clamps to hold 2 to 4 gels or broken gels in place. The gel
clamps are installed by inserting the them into the cutting tray slots at the front and back of the gel
tray (See Figure 4-1). The spring clip should be oriented to the front. The gel clamps should be slid
tightly up against the sides of glassed backed gels or directly on all other types of gels and blots.
Figure 4-1. Gel placement for: A, Single gels; B, Multiple gels.
5. Insert the gel tray into the spot cutter and make sure it is latched securely (see Section 2.4 by
pushing toward rear until it snaps in place.
4.2 PLASTIC AND GLASS-BACKED GELS
1. Store gels in a container that keeps them protected and hydrated until needed for spot cutting. Use
the gel manufacturer's recommended storage conditions. Dry the cutting sheet surface as well as the
back side of the plastic- or glass-backed gel to prevent the backing from sliding during the cut run.
2. Remove the gel tray from the spot cutter, then transfer the backed gel onto it.
3. If a single gel is being cut, position it in the middle of the gel tray (see Figure 4-1A). If two to four
small gels are being cut using the Analysis Set Excision Tool, position them as indicated on the
screen (see Figure 4-1B). Avoid excess water on the cutting sheet as this may cause the gel to float
and decrease the spot cutting performance.
4. Position the gel clamps on or against the gel or gel backing.
5. Insert the gel tray into the spot cutter and make sure it is latched securely (see Section 2.4).
A
B
GEL AND BLOT PREPARATION
4-1