Microfluidic chip devices and their use

A microfluidic chip device, comprising

• a microfluidic channel system comprising at least two reaction chambers interconnected with a channel having three or more liquid connections, the channel comprising sealable fluidic connections on both sides of the at least two reaction chambers, wherein the sealable fluidic connections act as inlets and/or outlets for a liquid stream,
• magnetic microbeads provided within at least one reaction chamber of the microfluidic channel system,
• wherein each reaction chamber comprises at least one microfluidic pillar filter within the reaction chamber, wherein the microfluidic pillar filter comprises pillar rods having interspaces sized to allow the magnetic microbeads to pass the interspaces one by one, and
• wherein the at least one microfluidic pillar filter filters bubbles formed in the liquid streams, and disintegrates clusters of magnetic microbeads.