An electrophoresis technique based on the movement of proteins through a stable pH gradient established using carrier ampholytes. Isoelectric focusing is the first dimension of 2-D electrophoresis.
The electrophoretic migration of proteins in a pH gradient to the pH at which they have no net charge (the isoelectric point). Proteins which diffuse away from the isoelectric pH become charged again and are electrophoresed back to their isoelectric pH (thus isoelectric focussing).
Technique for separating molecules by gel electrophoresis in a pH gradient subjected to an electric field. A protein migrates to the pH at which its overall net charge is zero.
Isoelectric focusing is a technique for separating molecules based on the relative charge contribution of their residues, isoelectric point (pI). Proteins are placed in a matrix (a gel slab) that is created with a pH gradient, and an electrical field is applied. The proteins migrate through the matrix to the point where the pH of the gel is the same as that of the protein, the isoelectric point. After separating and identifying proteins through this method, comparison of protein expression profiles can suggest proteins that contribute to health versus disease.
Method of mutation detection by which proteins are separated according to the pH at which their net charge is zero (isoelectric point); often used in conjunction with a western blot to allow identification of wild-type versus mutant protein products. A DNA sequence alteration resulting in an amino acid substitution can change the isoelectric point of a protein.
A separation principle that achieves separation by causing proteins or peptides to migrate under the influence of an electric through a pH gradient such that at a pH corresponding to their isoelectric points, they exhibit zero net charge and no longer respond to the electric field and stop migrating.
An analytical technique that uses electrophoresis in a pH gradient to determine the isoelectric point (pI, see below) of a polypeptide.
The first dimension of 2-D electrophoresis. IEF is the movement of proteins through a stable pH gradient with the use of ampholytes.
Isoelectric focusing, also known as electrofocusing, is a technique for separating different molecules by their electric charge differences. It is a type of zone electrophoresis, usually performed in a gel, that takes advantage of the fact that a molecule's charge changes with the p H of its surroundings.