High performance ion-exchange chromatography

The interaction of solute molecules with the ion-exchange stationary phase can be regarded as a sequential two-step process. Initially the solute must diffuse from the mobile phase (usually aqueous) into the stationary phase (often organic). The distribution between the two phases is largely responsible for the retention of a particular solute. Secondly, the solute must interact with, and diffuse through, the stationary phase. 

On ion-exchange resins the rate of diffusion through the stationary phase, to and from the ion-exchange site, is relatively slow. This slow mass transfer results in a large contribution towards band broadening. Pellicular materials with only a thin layer of resin were evolved to 

Most bonded phase ion-exchangers are stable up to 60 ° C and the speed of modem HPLC minimises the possibility of solute degradation. The k values for solutes frequently respond differently to changes in temperature and consequently this parameter can be used very effectively to modify the selectivity of the column. 

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The free oil can be determined by an ion exchange HPLC technique. A solution of the sample in ethyl alcohol is analysed by high-performance ion exchange chromatography using a specially prepared ion exchange resin stationary phase, ethanol mobile phase, and differential refractive index detection. 

Rounds, M. A. and Regnier, F. E., Evaluation of a retention model for high-performance ion-exchange chromatography using two different displacing... 

Kato, Y., Nakamura, K., Yamazaki, Y., and Hashimoto, T., Comparison of high-performance ion-exchange chromatography and gel electrophoresis in protein separations, ]. Chromatogr., 318, 358, 1985. 

Practical Strategies for Protein Contaminant Detection by High-Performance Ion-Exchange Chromatography... 

E. Jaime, C. Hummert, P. Hess and B. Luckas, Determination of paralytic shellfish poisoning toxins by high-performance ion-exchange chromatography, 7. Chromatogr., A, 929, 43-49 (2001). 

Regnier F (1984) High-performance ion-exchange chromatography, In Methods in Enzymology, Vol. 104, WB Jakoby, Ed., p. 170. Academic Press, Orlando FL. 

Horvath, C., High-Performance Ion-Exchange Chromatography with Narrow-Bore Columns Rapid Analysis of Nucleic Acid Constituents at... 

Arsenic is present mainly in ionic forms, which are usually separated by high-performance ion-exchange chromatography coupled to an atom- or isotope-specific... 

Schols, H.A., Reitsma, J.C.E., Voragen, A.G.J. and Pilnik, W. 1989. High-performance ion exchange chromatography of pectins, Food Hydrocolloids, 3 115-121. 

Figure 12.8 shows the high efficiency of high-performance ion-exchange chromatography by the rapid separation of 22 nucleotides and related compounds. Figure 12.9 is an example of the separation of RNA, DNA and a plasmid in a cell lysate on a wide-pore (400 nm) amino phase. 

P. R. Haddad and P. E. Jackson, The determination of ascorbate, bromate and metabisulfite in bread improvers using high performance ion-exchange chromatography. Food Tech. Aiist., 37,. 305,1985. 

High-Performance Ion-Exchange Chromatography with Narrow-Bore Columns Rapid... 

High-performance ion-exchange chromatography (HPIEC) is used to determine and quantify oxidized, deamidated, clipped or truncated forms of protein biopharmaceuticals based upon changes in product charge. 

Minear, R.A., Segars, J.E. and Elwood, J.W. (1988) Separation of inositol phosphates by high-performance ion-exchange chromatography. Analyst U3, 545-549. 

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