Ion-pairing chromatography

In a broader sense, the removal of interfering molecular species is not unique to GC analyses it has been widely practiced with many other biochemical and clinical determinations. For example, biomacromolecules can be denatured and precipitated through a variety of methods, or alternatively removed by gel-permeation chromatography prior to the sample analysis by GC. Additional purification methods may employ the acidobasic properties of either the interfering molecules, or a sample itself (pH manipulations, ion-exchange chromatography, ion-pairing extraction, etc.). Polar and nonpolar molecules can often be separated from each other in an easy manner as based on their different solubilities. 

Figure 2.23 Ion-pairing agents used in reversed phase chromatography. Ion-pairing agents illustrated in pink enhance the interaction of charged groups with the hydrophobic surface. They also suppress the ionization of residual silanols on silica-based reversed-phase media.

Analysis of barbiturates by reverse phase isocratic chromatography. Ion pair chromatography of vitamins. 

See also Ion Exchange Overview Principles Ion Chromatography Instrumentation Ion Chromatography Applications Isotope Separatbn. Liquid Chromatography Ion Pair. 

See also Electrophoresis Oven/iew Nucleic Acids. Liquid Chromatography ion Pair. 

Fig. 6-60. Selectivity comparison between ion-exchange chromatography, ion-pair chromatography and the combination of both on a multimode phase. - Separator columns OmniPac PAX-100, lonPac NSl and OmniPac PAX-500 eluant 42 mmol/L NaOH -t...

Spectrophotometry Ion exchange chromatography Ion pair chromatography Capillary electrophoresis Titration... 

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