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Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
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Development of a simple droplet-based microfluidic capillary viscometer for low-viscosity Newtonian fluids
Michael F DeLaMarre1, Alec Keyzer1, Scott A Shippy1
1Department of Chemistry, University of Illinois at Chicago, Illinois 60607, United States.
Analytical Chemistry
|April 1, 2015
Summary
This study introduces a microfluidic capillary viscometer that measures viscosity using droplet spacing. The device offers high accuracy, stability, and low sample volume requirements, simplifying viscosity measurements.
Area of Science:
- Fluid dynamics
- Analytical chemistry
- Microfluidics
Background:
- Viscosity is a crucial macroscopic property providing molecular insights, widely applied in science and engineering.
- Existing viscometry methods can be complex or require large sample volumes.
Purpose of the Study:
- To develop a novel microfluidic capillary viscometer for accurate and efficient viscosity measurements.
- To demonstrate the device's capability with low sample volumes and its applicability to various fluids.
Main Methods:
- A microfluidic device forms aqueous sample droplets in an immiscible carrier phase.
- Droplet spacing is used to encode and measure sample viscosity.
- Off-chip fluorescence detection is employed for viscosity determination.
Main Results:
- Exceptional calibration stability with only 0.6% drift.
- Operates with sample volumes as low as 38 nL for aqueous and nonaqueous samples.
- Accurate viscosity measurements (as low as 0.1% difference) compared to U-tube viscometry across a range of 0.96-52 cP.
Conclusions:
- The microfluidic viscometer offers a simple, stable, and accurate method for viscosity measurement.
- Its design facilitates integration with existing droplet-based platforms.
- Enables viscosity measurements of Newtonian fluids without stringent pressure or flow control.
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