title: Expandable microspheres for the handling of liquids.
abstract: Two novel concepts for controlled handling of liquids in microfluidic systems are presented: a one-shot micropump and a normally open one-shot valve based on thermo-expanding Expancel microspheres. Expancel microspheres are small spherical plastic particles that, when heated, increase their volume considerably. We show that liquid volumes in the nanoliter range can be actuated against a counter pressure of at least 100 kPa and fluid flow can be inhibited in a microchannel against pressures of at least 100 kPa.
authors.affiliation: Department of Signals, Sensors and Systems, Royal Institute of Technology, 100 44 Stockholm, Sweden.
authors.forename: Patrick
authors.initials: P
authors.lastname: Griss
authors.forename: Helene
authors.initials: H
authors.lastname: Andersson
authors.forename: Göran
authors.initials: G
authors.lastname: Stemme