Micropillar array chip for integrated white blood cell isolation and PCR

We report the fabrication of silicon chips containing a row of 667 pillars, 10 by 20 microm in cross-section, etched to a depth of 80 microm with adjacent pillars being separated by 3.5 microm. The chips were used to separate white blood cells from whole blood in less than 2 min and for subsequent PCR of a genomic target (eNOS). Chip fluid dynamics were validated experimentally using CoventorWare microfluidic simulation software. The amplicon concentrations were determined using microchip capillary electrophoresis and were >40% of that observed in conventional PCR tubes for chips with and without pillars. Reproducible on-chip PCR was achieved using white blood cell preparations isolated from whole human blood pumped through the chip.