IEF's greatest advantage is its high resolution, resulting in greater separation of solutes. IEF of serum proteins results in many more bands; these bands are sharper because each pH region is very narrow.
Performing IEF is easier because the placement of sample application is not important. The sample and ampholytes can be mixed before application; the ampholytes will migrate, create the gradient, and then the proteins separate and migrate.
Some isoenzymes and variant hemoglobins in prenatal screening are separated with IEF. Detection of oligoclonal bands in gamma-globulin is a newer use of IEF. IEF is commonly used as one of the separations in two-dimensional electrophoresis.