Use of 120-nm deep channels for liquid chromatographic separations

The present study reports on the exploration of the separation speed limits of RPLC chromatography in open-tubular channels. Applying the shear-driven chromatography principle in a 120-nm deep open channel, and using an improved detection set-up, the separation of three coumarin dyes was detectable 8 mm downstream of the injection point. At this distance, separation efficiencies of N = 17,900–24,100 plates were obtained at a velocity of 10 mm s−1, corresponding to a plate generation velocity of 21,100 to 28,300 plates per second for the most and least retained component, respectively.