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An electrically-controlled programmable microfluidic concentration waveform generator.

Joshua Garrison1, Zidong Li2, Barath Palanisamy2

  • 11Department of Electrical & Computer Engineering, University of California - Davis, Davis, CA 95616 USA.

Journal of Biological Engineering
|December 20, 2018
PubMed
Summary
This summary is machine-generated.

Researchers developed a microfluidic system using pulse width modulation (PWM) to accurately generate dynamic concentration waveforms for biological studies. This platform enables precise control over soluble factor levels, mimicking complex biological environments.

Keywords:
Concentration waveformMicrofluidicsPulse width modulationTime-varying soluble factors

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Area of Science:

  • Biomedical Engineering
  • Microfluidics
  • Cellular Biology

Background:

  • Biological systems exhibit complex, dynamic environmental conditions.
  • Studying cellular responses requires controlled, time-varying soluble factor concentrations.
  • Existing platforms lack the ability to generate arbitrary concentration waveforms.

Purpose of the Study:

  • To develop a microfluidic system capable of generating arbitrary time-varying concentration waveforms.
  • To address the need for precise control over soluble factor concentrations in biological research.
  • To enable studies on cellular responses to dynamic environmental stimuli.

Main Methods:

  • Developed a microfluidic system utilizing concepts from electrical engineering and fluid mechanics.
  • Employed pulse width modulation (PWM) for generating analog signals from digital sources.
  • Integrated laser-ablated microfluidic components: low-pass filter, resistor, and mixer, iteratively tuned for accuracy.

Main Results:

  • Successfully fabricated and characterized a microfluidic platform for generating time-varying concentrations.
  • Demonstrated the generation of accurate concentration waveforms (square, sawtooth, sinusoidal, triangle) for fluorescein.
  • Achieved waveform frequencies ranging from 100 mHz to 400 mHz.

Conclusions:

  • The microfluidic platform enables the generation of arbitrary concentration waveforms with high accuracy.
  • This technology is expected to advance biological studies involving dynamic soluble factor concentrations.
  • The platform holds potential for developing advanced biomedical devices for precise pharmaceutical dosing.