The possibility of generating high-speed shear-driven flows and their potential application in liquid chromatography

An experimental proof of principle is presented for the possibility to use a shear force field to generate a stable, chromatography enabling fluid flow through micrometer and submicrometer channels without the need for a pressure or a voltage gradient. In our setup, we were able to successfully move a color tracer plug at speeds exceeding 2 cm/s through a 0.125-microm-thick and 4-mm-wide channel, without creating a pressure drop or a pressure buildup. By showing that the speed of microchannel flows can be drastically increased by simply switching from one driving force to another, the presented experiments open the road to the development of a new type of chromatography, referred to as shear-driven chromatography, potentially offering unprecedented separation speeds and resolutions and complying perfectly with the present trend toward the miniaturization and parallelization of analytical separation equipment.