<Tr> <Th> Related </Th> <Td> Capillary electrophoresis SDS - PAGE Two - dimensional gel electrophoresis Temperature gradient gel electrophoresis </Td> </Tr> <P> Gel electrophoresis is a method for separation and analysis of macromolecules (DNA, RNA and proteins) and their fragments, based on their size and charge . It is used in clinical chemistry to separate proteins by charge and / or size (IEF agarose, essentially size independent) and in biochemistry and molecular biology to separate a mixed population of DNA and RNA fragments by length, to estimate the size of DNA and RNA fragments or to separate proteins by charge . </P> <P> Nucleic acid molecules are separated by applying an electric field to move the negatively charged molecules through a matrix of agarose or other substances . Shorter molecules move faster and migrate farther than longer ones because shorter molecules migrate more easily through the pores of the gel . This phenomenon is called sieving . Proteins are separated by charge in agarose because the pores of the gel are too large to sieve proteins . Gel electrophoresis can also be used for separation of nanoparticles . </P> <P> Gel electrophoresis uses a gel as an anticonvective medium and / or sieving medium during electrophoresis, the movement of a charged particle in an electrical field . Gels suppress the thermal convection caused by application of the electric field, and can also act as a sieving medium, retarding the passage of molecules; gels can also simply serve to maintain the finished separation, so that a post electrophoresis stain can be applied . DNA Gel electrophoresis is usually performed for analytical purposes, often after amplification of DNA via polymerase chain reaction (PCR), but may be used as a preparative technique prior to use of other methods such as mass spectrometry, RFLP, PCR, cloning, DNA sequencing, or Southern blotting for further characterization . </P>

The most common type of gel used for dna separation is