Orthogonal chromatography cross fractionation

Figure 15. Cross fractionation by orthogonal chromatography arrangement of...

D. Recommendations. Cross-Fractionation using Orthogonal Chromatography has high potential in the analysis of complex polymers and even polymer latices (with Hydrodynamic Chromatography). Multi-detector analysis, particularly utilizing spectrofluorometry, should be very useful in developing the technique. 

Balke ST, Patel RD (1983) Orthogonal chromatography. Polymer cross-fractionation by coupled gel permeation chromatographs. In Craver CD (ed) Polymer characterization. Adv Chem Ser 203, American Chemical Society, Washington, DC... 

CCC. A schematic diagram of the CCC system is shown in Figure 4 [this technique also has been named orthogonal chromatography 10-J3)]. Cross-fractionation on the polymer solution injected into the SEC column was performed on the solution passing through the switching valve in the time interval 830-850 s. This fraction was separated by isocratic elutions with column two. 

The method traditionally used for measuring the Bivariate Distribution is the "Chromatographic Cross Fractionation" (also referred to as "Two-dimensional Chromatography" or "Orthogonal Chromatography"). Macromolecules having different composition are separated in a silica column, and an SEC column is then used to elute chains having different sizes. ... 

Balke and Patel [62] used an orthogonal coupling of an SEC system to another HPLC system to achieve a desired cross-fractionation. They proposed to use it in an SEC/SEC mode, and suggested that a more descriptive general term for it is orthogonal chromatography . Both SEC systems utilized SEC columns. The solvent in the first system was chosen to accomplish only a hydrodynamic volume sreparation, and the solvent in the second system was chosen so as to be a thermodynamically poorer solvent for one of the monomer types in the copolymer in order to fractionate by composition under adsorption or partition modes as well as size exclusion. 

Some workers nsed SEC for the first fractionation, and TLC [2,3] and high-performance precipitation liqnid chromatography [4, 5] were applied as the second chromatographic method. Balke and Patel [6,7] performed cross-fractionation by orthogonal chromatography (SEC-SEC) in which different mobile phases were used. Tanaka and co-workers [8] used the... 

Combination of different separation techniques into a single experiment (multi-dimensional chromatography also called 2D chromatography, orthogonal chromatography, and cross-fractionation) has shown to overcome such types of limitations (see Section 9.5). 

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