Buffer isoelectric focusing revisited
1988; Elsevier BV; Volume: 440; Linguagem: Inglês
10.1016/s0021-9673(00)94540-0
ISSN1873-3778
AutoresPier Giorgio Righetti, M. Fazio, Carlo Tonani,
Tópico(s)Spectroscopy and Quantum Chemical Studies
ResumoIt has been experimentally demonstrated that buffer isoelectric focusing (IEF), as epitomized by the most elaborate mixture commercially available (Poly-Sep 47), cannot perform satisfactorily for the following reasons: (a) the mixture of buffers is too impoverished, amounting to less than eight species per pH unit (assuming a uniform pI distribution along the pH axis), when at least 20 amphoteres are needed per pH unit to generate a stepless pH course; (b) most of the amphoteric buffers commercially available (and present in the above mixture) have much too wide ΔpK values (in general well above 4 pH units) and therefore, at pH = pI, they cannot buffer and conduct the current, i.e., cannot be utilized as "carriers". Hence there seems to be no alternative, for a well behaved IEF system, to the random synthesis of carrier ampholytes (CA), as epitomized by the classical Vesterberg approach. In fact, the only valid alternative to conventional CA-IEF, and much superior, is the revolutionary methodology of immobilized pH gradients, as introduced in 1982 in the biochemical field.
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