Electrophoresis

Electrophoresis is used as a method of separating DNA according to size, using a porous gel as a filter. By applying an electric current, the molecules of DNA are made to move through the gel towards the positive electrode (anode), with the smaller or more compact strands travelling the fastest. This produces distinct bands of DNA, which can be identified by comparing with a known DNA sample 'ladder' run simultaeously. Any molecule with a net charge, such as proteins, can also be seperated using this technique.