A microfluidic timer for timed valving and pumping in centrifugal microfluidics

Abstract: Accurate timing of microfluidic operations is essential for the automation of complex laboratory workflows, in particular for the supply of sample and reagents. Here we present a new unit operation for timed valving and pumping in centrifugal microfluidics. It is based on temporary storage of pneumatic energy and time delayed sudden release of said energy. The timer is loaded at a relatively higher spinning frequency. The countdown is started by reducing to a relatively lower release frequency, at which the timer is released after a pre-defined delay time. We demonstrate timing for 1) the sequential release of 4 liquids at times of 2.7 s ± 0.2 s, 14.0 s ± 0.5 s, 43.4 s ± 1.0 s and 133.8 s ± 2.3 s, 2) timed valving of typical assay reagents (contact angles 36–78°, viscosities 0.9–5.6 mPa s) and 3) on demand valving of liquids from 4 inlet chambers in any user defined sequence controlled by the spinning protocol. The microfluidic timer is compatible to all wetting properties and viscosities of common assay reagents and does neither require assistive equipment, nor coatings. It can be monolithically integrated into a microfluidic test carrier and is compatible to scalable fabrication technologies such as thermoforming or injection molding

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Lab on a chip. 15 (2015), 1545-1553, DOI 10.1039/C4LC01269K, issn: 1473-0189 ; IN COPYRIGHT http://rightsstatements.org/page/InC/1.0 rs

Classification and Topics

• Classification: Ingenieurwissenschaften und Maschinenbau

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Albert-Ludwigs-Universität Freiburg
• (when): 2015
• Creator: Schwemmer, Frank ; Zehnle, Steffen ; Mark, Daniel ; Stetten, Felix von ; Zengerle, Roland ; Paust, Nils
• Contributor: Institut für Mikro- und Informationstechnik der Hahn-Schickard Gesellschaft für angewandte Forschung e.V ; Professur für Anwendungsentwicklung ; Technische Fakultät ; BIOSS Centre for Biological Signalling Studies ; Albert-Ludwigs-Universität Freiburg

Further information

• DOI: 10.1039/C4LC01269K
• URN: urn:nbn:de:bsz:25-freidok-121288
• Rights: Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:56 PM CET