Experimental Van Deemter plots of shear-driven liquid chromatographic separations in disposable microchannels

We present a new stationary phase coating method, yielding a monolayer of densely arrayed porous HPLC beads (dp=4 μm) for use in a disposable shear-driven flow LC system. The system is inherently suited for whole-column detection through the small voids between the individual particles of the layer. The chromatographic performance of the system has been characterized by performing a series of coumarin dye separation experiments (reversed-phase mode) and by measuring the theoretical plate height as a function of the mobile phase velocity. The resulting Van Deemter curve, yielding a value of about 90 000 plates/m near the u=uopt velocity, shows good agreement with the theoretical expectations, and hence constitutes the first full validation of the theory of shear-driven chromatography.