title: Electrochemical velocimetry on centrifugal microfluidic platforms.
abstract: Expanding upon recent applications of interfacing electricity with centrifugal microfluidic platforms, we introduce electrochemical velocimetry to monitor flow in real-time on rotating fluidic devices. Monitoring flow by electrochemical techniques requires a simple, compact setup of miniaturized electrodes that are embedded within a microfluidic channel and are connected to a peripherally-located potentiostat. On-disc flow rates, determined by electrochemical velocimetry, agreed well with theoretically expected values and with optical measurements. As an application of the presented techniques, the dynamic process of droplet formation and release was recorded, yielding critical information about droplet frequency and volume. Overall, the techniques presented in this work advance the field of centrifugal microfluidics by offering a powerful tool, previously unavailable, to monitor flow in real-time on rotating microfluidic systems.
authors.affiliation: Department of Biomedical Engineering, University of California, Irvine, Irvine, CA 92697, USA.
authors.forename: Kameel
authors.initials: K
authors.lastname: Abi-Samra
authors.forename: Tae-Hyeong
authors.initials: TH
authors.lastname: Kim
authors.forename: Dong-Kyu
authors.initials: DK
authors.lastname: Park
authors.forename: Nahui
authors.initials: N
authors.lastname: Kim
authors.forename: Jintae
authors.initials: J
authors.lastname: Kim
authors.forename: Hanshin
authors.initials: H
authors.lastname: Kim
authors.forename: Yoon-Kyoung
authors.initials: YK
authors.lastname: Cho
authors.forename: Marc
authors.initials: M
authors.lastname: Madou
mesh_terms: D002498:Centrifugation / Q000295:instrumentation*; D004560:Electricity; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D012212:Rheology / Q000295:instrumentation*; D012399:Rotation