Simple eluents for the formation of ascending pH gradients in chromatofocusing of bipolar compounds

Abstract

The formation of ascending pH gradients was studied in carboxyl columns with the use of eluents of simple composition (one or two components). The obtained gradients are comparable in a wide pH range with the gradient formed with the use of the synthetic polyampholytic eluent Polybuffer-96. The smoothest nearly linear pH gradients are formed at the ionic strength 0.05–0.5 in one or both mobile phases: the starting solution and the eluent. Potentialities of the analytical use of simple eluents in chromatofocusing were demonstrated with the example of the separation of a model mixture of proteins and formate dehydrogenase isoforms.