LIMITS OF RESOLUTION AND SPEED OF ANALYSIS IN LINEAR CHROMATOGRAPHY WITH AND WITHOUT FOCUSING

Previously [11], the theoretical limit of resolution in one class of chromatographic conditions was found and its proof was briefly outlined. Here, the theoretical limits of resolution and speed of analysis in any velocity-based separation of mixtures in a linear (nonoverloading) medium have been found. Rigorous proof of the limits is given. It has been shown that chromatographic focusing by negative velocity gradients cannot enhance resolution or speed of analysis beyond theoretical limits available without the focusing. On the other hand, the focusing can improve these characteristics if they were previously deteriorated due to non-ideal conditions of separation. However, the improvements can not go beyond the recovery of the losses of the otherwise deteriorated separation. In a broader sense, it has been shown that the theoretical limit of resolution and speed in any velocity-based separation of close solute pairs can not be enhanced by distance-based velocity gradients of any kind.