This document provides a protocol for agar electrophoresis. It lists the required materials which include agar powder, TAE buffer solution, gel chamber, comb, samples, and power supply. The process involves preparing the TAE buffer, casting the agar gel, loading colored samples into the wells, running the gel at 50V for 15 minutes, and observing how far the different samples migrate through the gel. The conclusion is that electrophoresis separates samples by size and charge, with smaller, more negatively charged components migrating farther towards the positive anode. By comparing the band patterns of crime scene and suspect samples, one sample matched the crime scene.

1. PROTOCOL FOR
AGAR
ELECTROPHORESIS
Jose Manuel Bocara

2. MATERIAL REQUIRED FOR THE PROCESS
1 g Agar 10 ml of TAE 50x
1 Erlenmeyer of at
least 100 ml
1 Bottle/recipient
of at least 100 ml
1 Scale (not provide
with the kit)
1 Microwave or hot
plate
Paper tissues or
gloves (not provide
with the kit)
500 ml of destilled
water (not provide
with the kit)

3. MATERIAL NEEDED FOR EACH PAIR OF
STUDENTS
1 Gel chamber
1 Comb with at
least 4 wells
2 Carbon papers
aprox. 4x1.5 cm
1 Syringe 4x10 ul tips
3x9 V batteries or a
power supply for
electrophoresis
2 Electric cables: 1
black, 1 red
4 Tubes with
coloured samples
1 Piece of black
and white paper
(A5 laminated)

4. PROCESSES OF ELABORATION

5. Prepare the TAE 1x solution
Dilute 10 ml of TAE
(concentration 50x) in 490 ml of
destilled water

6. Prepare your electrophoresis box
• Put the comb with 6
wells in the slot.
• Place your box on the
black paper

7. Prepare the Agar gel at 1%
• Weigh out 1 g of agar powder.
• Mix it with 100 ml of TAE 1x.
• Heat it in the microwave or on
a hotplate, until the solution
becomes transparent
1 2
3

8. A DIAGRAM

9. Load the samples
1. Cut off the gel that has gone over the litle wells using a ruler.
2. Put carbon paper over each end of the box.
3. Pour TAE 1x solution over the gel to cover it.
4. Remove the comb slowly and in a vertical position.
5. Get the syringe and put a 10 ul tip on the end.
6. Take out spproximately 10 ul of the first solution (to the second line marked on the tip).
7. Put the samples in the first well (or as was decided in point 4). Ensure your hand doesn't
shake.
8. Load the other samples into the other wells and do not forget to change your tip each time

10. Load of Samples images

11. Run the Gel
Connect 3.9 V batteries
in series
Or set the power supply
at 50 V
Connect the cables,
using the colour code:
Black-negative side on
the top, close to the
samples Red-positive
side, at the bottom, far
away from the samples.
Turn on the power (run
button)
Wait approximately 15
minutes, until different
bands appear.

12. Run the Gel images

13. Observation
The samples were composed
of different colours, each
colour moves at a different
specific speed in the gel,
attracted by the positive
pole.
S1 EC S3 S2

14. Result
Place your box on white
paper so you can see the
result more clearly

15. Conclusion
• Electrophoresis is a technique that allows us to separate
components by size
• We can see that some of the samples have 2 components and others
have 3.
• The yellow component is the smallest and is the most negatively
charged as it moves the furthest through the gel towards the positive
anode.
• The blue components is the largest and has the least negative charge
as it moves the least through the gel.
Conclusion:
Sample S3 has the same
components as the crime
Scene (EC) sample.
S1 EC S3 S2

16. END OF PROTOCOL
Jose Manuel Bocara