Agarose gel electrophoresis

Digital image of 3 plasmid restriction digests run on a 1% w/v agarose gel, 3 volt/cm, stained with ethidium bromide. The DNA size marker is a commercial 1 kbp ladder. The position of the wells and direction of DNA migration is noted.

Agarose gel electrophoresis is a method of gel electrophoresis used in biochemistry, molecular biology, genetics, and clinical chemistry to separate a mixed population of macromolecules such as DNA or proteins in a matrix of agarose, one of the two main components of agar. The proteins may be separated by charge and/or size (isoelectric focusing agarose electrophoresis is essentially size independent), and the DNA and RNA fragments by length.[1] Biomolecules are separated by applying an electric field to move the charged molecules through an agarose matrix, and the biomolecules are separated by size in the agarose gel matrix.[2]

Agarose gel is easy to cast, has relatively fewer charged groups, and is particularly suitable for separating DNA of size range most often encountered in laboratories, which accounts for the popularity of its use. The separated DNA may be viewed with stain, most commonly under UV light, and the DNA fragments can be extracted from the gel with relative ease. Most agarose gels used are between 0.7–2% dissolved in a suitable electrophoresis buffer.

  1. ^ Kryndushkin DS, Alexandrov IM, Ter-Avanesyan MD, Kushnirov VV (December 2003). "Yeast [PSI+] prion aggregates are formed by small Sup35 polymers fragmented by Hsp104". The Journal of Biological Chemistry. 278 (49): 49636–43. doi:10.1074/jbc.M307996200. PMID 14507919.
  2. ^ Sambrook J, Russel DW (2001). Molecular Cloning: A Laboratory Manual 3rd Ed. Cold Spring Harbor Laboratory Press. Cold Spring Harbor, NY.