Analytical and Bioanalytical Chemistry

, Volume 411, Issue 21, pp 5393–5403 | Cite as

An investigation into the kinematics of magnetically driven droplets on various (super)hydrophobic surfaces and their application to an automated multi-droplet platform

  • Prashant Agrawal
  • Kyle J. Bachus
  • Gabrielle Carriere
  • Phoenix Grouse
  • Richard D. OleschukEmail author
Research Paper
Part of the following topical collections:
  1. Ultrasmall Sample Biochemical Analysis


Magnetic actuation on digital microfluidic (DMF) platforms may provide a low-cost, less cumbersome alternative for droplet manipulation in comparison to other techniques such as electrowetting-on-dielectric. Precise control of droplets in magnetically driven DMF platforms is achieved using a low-friction surface, magnetically susceptible material/droplet(s), and an applied magnetic field. Superhydrophobic (SH) surfaces offer limited friction for aqueous media as defined by their high water contact angles (WCA) (>150°) and low sliding angles (<10°). The low surface friction of such coatings and materials significantly reduces the force required for droplet transport. Here, we present a study that examines several actuation parameters including the effects of particle and particle-free actuation mechanisms, porous and non-porous SH materials, surface chemistry, droplet speed/acceleration, and the presence of surface energy traps (SETs) on droplet kinematics. Automated actuation was performed using an XY linear stepper gantry, which enabled sequential droplet actuation, mixing, and undocking operations to be performed in series. The results of this study are applied to a quantitative fluorescence-based DNA assay in under 2 min.

Graphical abstract


Magnetic actuation Superhydrophobic Droplet DNA quantitation 



The authors would like to extend their gratitude to Dr. Guojun Liu’s research group at Queen’s University for assisting with contact angle measurements and NanoFabrication Kingston where the laser micromachining was performed. The authors would also like to acknowledge the funding bodies, namely CMC Microsystems for its microfabrication support, the Canadian Foundation for Innovation (emSYSCAN Project) for infrastructure (XY gantry), and Natural Sciences and Engineering Research Council for Discovery Grant Funding.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Prashant Agrawal
    • 1
  • Kyle J. Bachus
    • 1
  • Gabrielle Carriere
    • 1
  • Phoenix Grouse
    • 1
  • Richard D. Oleschuk
    • 1
    Email author
  1. 1.Department of ChemistryQueen’s UniversityKingstonCanada

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