Dispersion in Sorption and Elution

Here the term dispersion is used in a more general sense, not only referring to the spatial distribution of the analyte in solution, but also in the column. The dispersion of the analyte during sorption and elution is influenced by at least the following factors  

On-line columns packed with inert packing materials usually have very limited effect on the dispersion of an injected sample. When an active sorptive material is substituted in the column, the sorbent contributes significantly to the dispersion characteristics of the sorbed analyte. Despite the differences between FI column preconcentration and HPLC discussed in Chapter 1, the sorption and release of the analyte in FI on-line column is in principle a chromatographic process, and it may be used to predict and explain the dispersive behavior of the analyte within this sequence. 

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