Isoelectric Focussing

This technique is primarily based on the immobilization of the molecules at isoelectric pH during electrophoresis. Stable pH gradients are set up (Usually in a gel) covering the pH range to include the isoelectric points of the components in a mixture. as the electrophoresis occurs, the molecules migrates to positions corresponding to their isolelctric points, get immobilized and form sharp stationary bonds. the gel blocks can be stained and identified. by isoelectric focussing, serum proteins can be separated to as many as 40 bonds. Isoelectric focussing can be conveniently used for the purification of proteins.
Source : Biochemistry by Dr. U. Satyanarayana