Electrophoresis

Electrophoresis through agarose is a standard method used to separate, identify and purify DNA fragments. The method is simple and rapid to do and capable of resolving fragments of DNA that cannot be separated adequately by other procedures.

Gel electrophoresis is a technique used for the separation of nucleic acids and proteins. Separation of macromolecules depends upon two variables: charge and mass. When a biological sample such as DNA is mixed in a buffer solution and applied to a gel, these two variables act together. The electric current from one electrode repels the molecules while the other electrode simultaneously attracts the molecules. The friction force of the gel material acts as a molecular sieve, separating the molecules by size.

During electrophoresis, macromolecules are forced to move through the pores and their rate of migration through the electric field depedns on the following:
-strength of the field
-size and shape of the molecules
-relative hydrophobicity of the samples
- ionic strength and temperature of the buffer in which the molecules are moving.