Isoelectric focusing, blotting and probing methods for detection and identification of monoclonal proteins.

Isoelectric focusing (IEF) is a technique of exquisite resolution and high sensitivity. When applied to human biological fluids using conventional protein stains it is capable of detecting down to about 100 mg of protein/L. When combined with blotting and probing techniques it can get down to less than 1 mg/L.