LABORATORY SKILLS TRAINING
TITLE:
CASTING AGROSE GELS FOR ELECTROPHORESIS
PURPOSE:
The purpose of this Skills Training is to train the student in making
an agarose solution and casting gels for horizontal gel
electrophoresis.
PREREQUISITES:
Understanding of how to make a diluted buffer solution.
REFERENCES:
N/A
MATERIALS:
Agarose powder
Weigh boats or weigh paper
Hot plate with magnetic stir capabilities
Magnetic stir bar and stir bar removal tool
Electronic Balance
Casting Gel Trays
Gel Tray Dams or Black Electrical Tape
Combs (per experiment requirements; 8 teeth, 12 teeth etc.)
1X Electrophoresis Buffer Solution
Erlenmeyer flask (~500 mL and depends on volume of agarose
solution being made).
SAFETY EQUIPMENT:
PPE: Lab coat, safety glasses, gloves
PROCEDURE: Casting Gels for Electrophoresis
Part I: Making an Agarose Solution
1. Determine the desired percent concentration of the gel. A 0.8% agarose concentration is
typical for horizontal gel electrophoresis but does vary depending on the type of
experiment.
Note: 0.8% means there are 0.8 grams of agarose in every 100 mL of solvent (i.e. buffer). If
200 mL of a 0.8% agarose solution needs to be made then 1.6 grams of agarose will be dissolved
into 200 mL of buffer etc.
CCCLST0051
Approved: 27July2014
Revision:
2. Determine the total number of gels required. For six gels 300 mL of agarose molten
solution is sufficient.
3. Place a stir bar into a 500 mL Erlenmeyer flask.
4. Measure 300 mL of 1X electrophoresis buffer into the flask.
5. Weigh 2.4 grams of agarose powder and add to the buffer. Swirl to initially mix the
solution. The solution will be cloudy.
Note: Adding 2.4 grams of agarose to 300 mL of electrophoresis buffer makes a 0.8% agarose
gel. Adding agarose powder to the buffer prevents clumping.
6. Place the agarose solution on a hot plate, turn heat on and magnetic stir capabilities.
Note: Do not take your eyes off of the hot plate while the agarose is becoming a molten
solution. The agarose solution can boil over quickly.
Part II: Casting the Gel in the Gel Tray
1. While the agarose is heating, prepare the casting gel trays with dams or black electrical
tape at each end to make the mould for the gel. Make sure if you are using tape that the
tape is flat and secure along the entire edge surface to prevent leaks.
2. Select a comb to accommodate the number of wells and volume of sample needed.
Note: Be sure all gel trays are flat and level and combs in place.
3. Remove the agarose when the molten solution is completely transparent but BEFORE it
boils.
4. Place a thermometer in the molten agarose.
5. Cool the molten agarose until ~65oC. If the agarose has not cooled sufficiently, the
casting trays can warp over time.
6. When cooled sufficiently, pour agarose into casting tray to desired thickness using
approximately 40 mL of molten agarose for each tray. Pour until the agarose reaches
midway to the top of the tray.
7. Allow agarose to harden and then remove combs and dams/tape carefully. Leave gel in
the tray.
8. Gels are ready for electrophoresis studies.
Note: If gels are not going to be used within two hours, leave dams/tape and comb in place (do
not remove) and cover with a small amount of buffer to prevent drying. Wrap in plastic wrap
and keep in the refrigerator until needed. Gels will keep for at least a week.
CCCLST0051
Approved: 27July2014
Revision:
TRAINING ASSESSMENT:
The laboratory technician is considered trained in Casting
Gels for Electrophoresis when they have successfully
completed the training assessment.
1. Appropriate use of the SOP for casting gels for
electrophoresis and indicated through PLD in
the laboratory notebook.
DOCUMENTATION:
Evaluations as noted above are recorded in the students
training notebook and in the Skills Training Assessment
Log.
DOCUMENTATION OF SKILLS TRAINING:
Student Name: ________________________
Date: __________________________
Approved By: _________________________
Date: __________________________
CCC Science Department Instructor
CCCLST0051
Approved: 27July2014
Revision: