Phase change microvalve for integrated devices.

Rohit Pal; Ming Yang; Brian N Johnson; David T Burke; Mark A Burns

doi:10.1021/ac0352934

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Phase change microvalve for integrated devices.

Rohit Pal·Ming Yang·Brian N Johnson·David T Burke·Mark A Burns

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Abstract

An active microvalve that uses a meltable piston in place of a conventional solid material to obstruct fluid flow in a microfluidic channel has been developed. This phase change valve is simple to operate and requires no additional fabrication steps. The valve is inherently latched, reusable, and leak-proof (to at least 250 psi) and can be electronically addressed using resistive heaters. The valve has been characterized for a range of operational parameters that will serve as a design guide. For the designs tested, piston displacements of 5 mm or more in 1 s have been achieved. Valves 1.4 mm in length in a 50 microm x 200 microm channel have been integrated on a biochemical reaction device, and successful DNA amplification using PCR has been achieved. The phase change valve can be easily implemented in an array format that can be used to realize complex microfluidic circuits.

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Glass Membranes, Artificial Microfluidics Polymerase Chain Reaction Pressure Sensitivity and Specificity Silicones Surface Properties Temperature Time Factors Journal Article Research Support, U.S. Gov't, P.H.S.

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Rohit Pal, Ming Yang, Brian N Johnson, David T Burke, Mark A Burns. 2004-07-01. Phase change microvalve for integrated devices.. https://doi.org/10.1021/ac0352934

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