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Updated: Apr 3, 2026

Microfluidic Chips Controlled with Elastomeric Microvalve Arrays
Published on: October 1, 2007
Highly responsive core-shell microactuator arrays for use in viscous and viscoelastic fluids
Briana L Fiser1, Adam R Shields1, M R Falvo1
1Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (USA).
Abstract:
We present a new fabrication method to produce arrays of highly responsive polymer-metal core-shell magnetic microactuators. The core-shell fabrication method decouples the elastic and magnetic structural components such that the actuator response can be optimized by adjusting the core-shell geometry. Our microstructures are 10 μm long, 550 nm in diameter, and electrochemically fabricated in particle track-etched membranes, comprising a poly(dimethylsiloxane) core with a 100 nm Ni shell surrounding the upper 3-8 μm. The structures can achieve deflections of nearly 90° with moderate magnetic fields and are capable of driving fluid flow in a fluid 550 times more viscous than water.
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