BL4840

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BL4840
(Molecular Biology techniques)

• Lab 2 09/08/05

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Lab2

• 1. Electrophoresis
• 2. Southern blotting

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1.Electrophoresis

• Agarose gel separates DNA fragments according to
  their relative size and shape. You must load DNA
  near the negative electrode.
• EB ethidium bromide, fluorescent dye to detect
  DNA fragments.
• Function of Loading buffer (1) help the sample
  sink to the bottom of the well (2) indicate how
  much the gel has been run

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2. Southern blotting

• Depurination makes DNA into smaller fragments. If
  the fragments are small, this step is no need.
• SSC standard sodium citrate, provides high salt
  level for DNA transferring.
• Be sure to cut the gel out of the nylon membrane.

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Probably helpful information

• Some factors to be considered running a
  gel (1) Agarose concentration If you want
  resolve small DNA, use higher concentrations of
  agarose. (2) Voltage Lower voltage usually
  produce better resolution (3) electrophoresis
  buffer provide pH and ionic strength providing
  conductivity too high concentration will lead to
  melt the gel when run it.

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pBR322 restriction map