Viscoelastic Particle Train Formation in Microfluidic Flows Using a Xanthan Gum Aqueous Solution
Anoshanth Jeyasountharan1, Keshvad Shahrivar1, Gaetano D'Avino2
1Systems and Process Engineering Centre, College of Engineering, Swansea University, Fabian Way, Swansea SA1 8EN, U.K.
Analytical Chemistry
|March 23, 2021
Summary
Viscoelastic shear-thinning xanthan gum solutions create ordered particle trains in microfluidic devices. Reducing particle concentration and simplifying sample introduction enhances train uniformity for applications like droplet encapsulation.
Area of Science:
- Fluid Dynamics
- Materials Science
- Biophysics
Background:
- Viscoelastic polymer solutions are crucial for microfluidic particle and cell manipulation.
- Viscoelasticity induces hydrodynamic interactions, forming particle trains with preferential spacing.
- Limited experimental data exists on viscoelastic ordering phenomena.
Purpose of the Study:
- To investigate particle train self-assembly in a viscoelastic shear-thinning xanthan gum solution.
- To analyze particle spacing and the factors influencing train uniformity.
- To optimize microfluidic systems for applications requiring ordered particle streams.
Main Methods:
- Utilized a serpentine microfluidic device with a circular cross-section.
- Employed a viscoelastic shear-thinning aqueous xanthan gum solution.
- Quantified interparticle distances and analyzed particle string formation (doublets, triplets).
Main Results:
- Demonstrated self-assembly of particle trains on the microfluidic centerline.
- Observed particle reorganization into aligned structures with preferential spacing.
- Found that increased local particle concentration leads to more doublets and triplets.
- Showed that a single sample introduction tube significantly reduces multi-particle strings.
Conclusions:
- Viscoelastic xanthan gum solutions effectively drive particle train formation in microfluidics.
- Local particle concentration and sample introduction method impact train uniformity.
- Findings support optimized droplet encapsulation and flow cytometry using controlled particle trains.
