The Alpher, Bethe, Gamow of isoelectric focusing, the alpha-Centaury of electrokinetic methodologies. Part I.
The birth and evolution of IEF in conventional carrier ampholyte buffers is reviewed here, from a shaky start during World War II, via desperate attempts of Svensson to create pH gradients by stationary electrolysis of salts, to the development of the IEF theory and the solution of the steady-state equation. The remarkable synthetic process of Ampholines, as ingeniously devised by Vesterberg, is additionally recalled, with a thorough description of the fundamental properties of these amphoteric buffers, creating and maintaining the pH gradient under strong electric fields. The review ends with a mention of the major contributions of B. J. Radola to this field, namely analytical and preparative IEF in granulated Sephadex layers and the development of ultrathin IEF, in polyacrylamide gels as thin as 20-100 mum. The latter technique paved the way to DNA sequencing gels and to CZE. The symptoms of decay are here presented through the simulations of Mosher and Thormann, clearly indicating an isotachophoretic mechanism for pH gradient decay with time. The decay of IEF was the birth of IPGs.
Righetti
Pier Giorgio
PG
Politecnico di Milano, Department of Chemistry, Materials and Engineering Chemistry Giulio Natta, Milano, Italy. piergiorgio.righetti@polimi.it
D000180:Acrylic Resins; D000665:Ampholyte Mixtures; D002021:Buffers; D003911:Dextrans; D049673:History, 20th Century; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing / Q000266:history / Q000379:methods*
D000180:Acrylic Resins; D000665:Ampholyte Mixtures; D002021:Buffers; D003911:Dextrans; C016680:polyacrylamide gels; C025614:sephadex