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Tunable-delay shunts for paper microfluidic devices.

ABSTRACT: We demonstrate a novel method for controlling fluid flow in paper-based devices. The method delays fluid progress through a porous channel by diverting fluid into an absorbent pad-based shunt placed into contact with the channel. Parameters to control the delay include the length and the thickness of the shunt. Using this method, reproducible delays ranging from 3 to 20 min were achieved. A simple electrical circuit model was presented and used to predict the delays in a system. Results from the model showed good agreement with experimental observations. Finally, the shunts were used for the sequential delivery of fluids to a detection zone in a point-of-care compatible folding card device using biochemical reagents for the amplified detection of the malaria protein PfHRP2.

SUBMITTER: Toley BJ

PROVIDER: S-EPMC3950207 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Tunable-delay shunts for paper microfluidic devices.

Toley Bhushan J BJ McKenzie Brittney B Liang Tinny T Buser Joshua R JR Yager Paul P Fu Elain E

Analytical chemistry 20131118 23

We demonstrate a novel method for controlling fluid flow in paper-based devices. The method delays fluid progress through a porous channel by diverting fluid into an absorbent pad-based shunt placed into contact with the channel. Parameters to control the delay include the length and the thickness of the shunt. Using this method, reproducible delays ranging from 3 to 20 min were achieved. A simple electrical circuit model was presented and used to predict the delays in a system. Results from the ...[more]

PMID: 24245747

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