A Parylene MEMS Electrothermal Valve.

J Microelectromech Syst

Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 USA ( ).

Published: December 2009

The first microelectromechanical-system normally closed electrothermal valve constructed using Parylene C is described, which enables both low power (in milliwatts) and rapid operation (in milliseconds). This low-power valve is well suited for applications in wirelessly controlled implantable drug-delivery systems. The simple design was analyzed using both theory and modeling and then characterized in benchtop experiments. Operation in air (constant current) and water (current ramping) was demonstrated. Valve-opening powers of 22 mW in air and 33 mW in water were obtained. Following integration of the valve with catheters, our valve was applied in a wirelessly operated microbolus infusion pump, and the in vivo functionality for the appropriateness of use of this pump for future brain mapping applications in small animals was demonstrated.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3042720PMC
http://dx.doi.org/10.1109/JMEMS.2009.2031689DOI Listing

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