Microfluidic chip with movable layers for the manipulation of biochemicals.

A simple and effective platform that can conglomerate various microfluidic functions in a single chip is essential for many bioassays, especially for point-of-care testing applications. Here, a chip that exploits surface tension in solutions with movable top and bottom layers is presented, for use in fluid transport, mixing, maintaining metered volumes, and biomolecule capture and release. The chip has open chambers in vertically mobile top layers and rotationally mobile bottom layers to exploit surface tension in biochemical solutions, and implements control over fluid motion. To manipulate biomolecules, a vertically mobile tip with a permanent magnet at the top layer performs collection, transport, release, and dispersion of magnetic beads. Thus, the chip orchestrates various fluidic control functions without using on-chip valves and pumps that increase operational and structural complexity. To demonstrate its utility, the chip performs automated DNA extraction by obtaining genomic DNA from a sample containing cells. Our approach provides a useful and effective alternative to numerous platforms that use active and passive on-chip components for bioassays.