DNA Structure
and Analysis
Activity 4.3: Dye Electrophoresis
Activity 4.3: Dye Electrophoresis
 Research questions:
– What charge do dyes have?
– Are samples composed of multiple dyes?
 Objectives:
– Load and run dyes on an agarose gel
– Determine the charge of each
electrophoresed dye
– Determine the composition of each colored
sample
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Safety Reminders
 Follow all laboratory safety procedures
– Appropriate PPE should be worn at all times
– Attention should be given when using electricity in the
presence of liquids. If there are leaks in equipment,
notify teacher immediately
– Turn off power before removing lid and ensure that lid
is in place before turning power on
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Skills to Master
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Set up a horizontal gel electrophoresis chamber
Load an agarose gel submerged in running buffer
Perform agarose gel electrophoresis
Program and utilize a power supply
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Running an Agarose Gel
 Play video: Agarose Gel Electrophoresis
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Student Workstation Materials
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Protocol Highlights/Tips
 If you are extracting dyes from
candy, extract in 5% glycerol
 Extract in the smallest amount of
glycerol possible to ensure dyes
are concentrated
 If using food coloring make a
0.25% v/v solution using 5%
glycerol as diluent
 Ready-made loading dyes
should be used at 1x
concentration
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Summary
 Make sure to:
– Record all steps in your notebook
– Ensure all lane contents are
recorded in an organized manner in
your notebook
– Record the power supply settings
and times in your notebook
– Place the micropipet tip just under
the surface of the running buffer
and deliver the dye into the well.
Do not try to get the tip into the
well. It could pierce the bottom of
the well or break the side
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