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Constant flow-driven microfluidic oscillator for different duty cycles.

ABSTRACT: This paper presents microfluidic devices that autonomously convert two constant flow inputs into an alternating oscillatory flow output. We accomplish this hardware embedded self-control programming using normally closed membrane valves that have an inlet, an outlet, and a membrane-pressurization chamber connected to a third terminal. Adjustment of threshold opening pressures in these 3-terminal flow switching valves enabled adjustment of oscillation periods to between 57 and 360 s with duty cycles of 0.2-0.5. These values are in relatively good agreement with theoretical values, providing the way for rational design of an even wider range of different waveform oscillations. We also demonstrate the ability to use these oscillators to perform temporally patterned delivery of chemicals to living cells. The device only needs a syringe pump, thus removing the use of complex, expensive external actuators. These tunable waveform microfluidic oscillators are envisioned to facilitate cell-based studies that require temporal stimulation.

SUBMITTER: Kim SJ

PROVIDER: S-EPMC3264749 | biostudies-other | 2012 Jan

REPOSITORIES: biostudies-other

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Constant flow-driven microfluidic oscillator for different duty cycles.

Kim Sung-Jin SJ Yokokawa Ryuji R Lesher-Perez Sasha Cai SC Takayama Shuichi S

Analytical chemistry 20111229 2

This paper presents microfluidic devices that autonomously convert two constant flow inputs into an alternating oscillatory flow output. We accomplish this hardware embedded self-control programming using normally closed membrane valves that have an inlet, an outlet, and a membrane-pressurization chamber connected to a third terminal. Adjustment of threshold opening pressures in these 3-terminal flow switching valves enabled adjustment of oscillation periods to between 57 and 360 s with duty cyc ...[more]

PMID: 22206453

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Constant flow-driven microfluidic oscillator for different duty cycles.

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Constant flow-driven microfluidic oscillator for different duty cycles.

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