Patent ID: 8652420

Claim:
A chromatographic separation device comprising, directly extending into each other in the fluid flow direction: a) an inlet channel; b) optionally, an open region of 1-20 μm; c) a first flow distribution region that is filled with an array of micro-fabricated pillars, the width of said first flow distribution region being more than doubled with respect to the width of said inlet channel and whereby said pillars have a diamond-like or ellipsoidal shape with a ratio of lateral width to axial width that is larger than 3/2, said pillars are in a diagonal alternating arrangement forming laterally extending interconnected channels, and the size and the positioning of said pillars is such that said first flow distribution region has a ratio of transversal to axial permeability of at least 2; d) a micro-fabricated separation channel; e) a second flow distribution region that is filled with an array of micro-fabricated pillars, whereby said pillars have a diamond-like or ellipsoidal shape with a ratio of lateral width to axial width that is larger than 3/2, said pillars are in a diagonal alternating arrangement forming laterally extending interconnected channels, and the size and the positioning of said pillars is such that said second flow distribution region has a ratio of transversal to axial permeability of at least 2; and e) an outlet channel; the width of said second flow distribution region being more than doubled with respect to the width of said outlet channel; wherein said micro-fabricated separation channel comprises a micro-pillar array with micro-pillars substantially smaller in diameter than the micro-fabricated pillars of said first and said second flow distribution region.