Dictionary > Electrophoresis

Electrophoresis

Electrophoresis
(Science: technique) separation of ionic molecules, (principally proteins) by the differential migration through a gel according to the size and ionic charge of the molecules in an electrical field. High resolution techniques normally use a gel support for the fluid phase.
Examples of gels used are starch, acrylamide, agarose or mixtures of acrylamide and agarose. Frictional resistance produced by the support causes size, rather than charge alone, to become the major determinant of separation.
Smaller molecules with a more negative charge will travel faster and further through the gel toward the anode of an electrophoretic cell when high voltage is applied. Similar molecules will group on the gel. They may be visualised by staining and quantitated, in relative terms, using densitometers which continuously monitor the photometric density of the resulting stain.
The electrolyte may be continuous (a single buffer) or discontinuous, where a sample is stacked by means of a buffer discontinuity, before it enters the running gel/ running buffer. The gel may be a single concentration or gradient in which pore size decreases with migration distance.
in sds gel electrophoresis of proteins or electrophoresis of polynucleotides, mobility depends primarily on size and is used to determined molecular weight. In pulse field electrophoresis, two fields are applied alternately at right angles to each other to minimise diffusion mediated spread of large linear polymers.
See: electrofocussing, pulse field electrophoresis


You will also like...

Cell Biology
Cell Biology

The cell is defined as the fundamental, functional unit of life. Some organisms are comprised of only one cell whereas o..

"Cronopio dentiacutus", a prehistoric mammal (an illustration)
Mammalian Ancestors

Mammals are a diverse group of organisms, where most of them develop their offspring within the uterus of the mother. Ov..

dinosaurs
The Dinosaurs

Dinosaurs represented a major turn in the evolutionary development of organisms on Earth. The first dinosaurs were presu..

Early Mammals on Earth
Early Mammals on Earth

The Earth's ecosphere was rapidly changing and throwing up a wide range of ecological niches that new adaptive organisms..

An artist's depiction of the origin of amphibians
Amphibians & Early Reptiles

Obtaining air outside an aquatic environment required species to acquire suitable adaptations, and this was the case of ..

Growth and Plant Hormones
Growth and Plant Hormones

Plants, like animals, produce hormones to regulate plant activities, including growth. They need these hormones to respo..