Simultaneous cell lysis and bead trapping in a continuous flow microfluidic device

Continuous flow cell lysis by electroporation (EP), and cell and bead trapping by dielectrophoresis (DEP) have been demonstrated on a dielectrophoretic microfluidic chip. The results of lysing human white blood cells (WBC) and murine clonal cells (MN9D) by electroporation showed that lysis rates of up to 80% were achieved at 3 MHz and a flow rate of 30 mu l/min. It was also shown that the lysis reactor can function as a dielelectrophoretic filter for trapping silica beads which selectively bind to DNA. The combination of cell lysis, DNA binding to beads, and bead separation assay in a single structure offers a step forward in the development of an efficient and compact system for fully automated microfluidic DNA sample preparation. The continuous flow protocol addresses major challenges faced in sample preparation such as lysate clogging, cell sedimentation, and cell agglomeration. (c) 2005 Elsevier B.V. All rights reserved.