Electrophoresis is an analytical technique for the analysis of macromolecules like proteins and nucleic acids. This technique was discovered and first used in 1937 by a Swedish biochemist Arne Tiselius . The electrophoretic effect is based on the theory of Debye - Huckel - Onsager where this theory of electrolytic dissociation accept the fact that charged particles move up under the influence of electrostatic forces to an electrode of opposite charge is applied when a potential difference in a solution containing electrolytes. Electrophoresis is the migration of a charged molecule under the influence of an electric field . The electrophoretic mobility is given by :
μ = v / E = Z / f
The electrophoretic mobility ( μ ) is the ratio between the speed ( v) the macromolecule and the electric potential ( E) that moves the macromolecule or the ratio of the net charge (Z) and the friction coefficient (f).
Media for electrophoresis
The media commonly used for electrophoresis are polyacrylamide gels for proteins and nucleic acids in agarose by virtue of these polymers function as a molecular sieve , or separate species due to its size and molecular weight , respectively , inhibits propagation of heat due to the friction caused by the migration and application of electric field.
Polyacrylamide gels are commonly used for protein separation by virtue of being chemically inert , easy staining with silver nitrate and Coomassie blue dye (dyes such as agarose stain completely prevented the identification of species in the electrophoretogram ) , the pores are easyly adjustable through control of acrylamide and bis- acrylamide are polymers that form the gel.
The agarose gels are used for macmoléculas with a molecular weight greater tha...
... middle of paper ...
... focusing is placed horizontally on an SDS gel , the electric field is applied and the protein macromolecules are separated acrodo with the isoelectric point and in terms of its molecular mass , providing a electrophoretogram that enables viewing and identification of many proteins at once .
Two-dimensional electrophoresis or 2D
This technique offers better resolution , or a higher level of detail at the end of which combines electrophoretogram isoelectric focusing and SDS gel electrophoresis . According to the scheme below :
In two-dimensional electrophoresis gel of isoelectric focusing is placed horizontally on an SDS gel , the electric field is applied and the protein macromolecules are separated acrodo with the isoelectric point and in terms of its molecular mass , providing a electrophoretogram that enables viewing and identification of many proteins at once .