The Conditions for Chromatographic Separation

Marcel Dekker, Inc. 270 Madison Avenue, New York, New York 10016 

It follows that for two solutes (A) and(B) to be separated if their retention volumes differ, 

The extent to which two solutes are separated depends exclusively on the relative magnitudes of their individual distribution coefficients (K(a)) and (K(b)) and the amount of stationary phase with which they can interact, (V(a)) and (V(b)). Consequently, for them to be separated, either their distribution coefficients must differ (choose appropriate phase systems), the amount of stationary phase with which they interact must differ (choose a stationary phase with exclusion properties), or a subtle combination of both. 

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