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Microfluidic Formation of Membrane-Free Aqueous Coacervate Droplets in Water
Dirk van Swaay1, T-Y Dora Tang2, Stephen Mann3
1Institute for Chemical and Bioengineering, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich (Switzerland).
Angewandte Chemie (International Ed. in English)
|May 28, 2015
Summary
Microfluidic flow-focusing creates stable coacervate droplets with precise size control. This method enables the creation of cell-mimicking compartments for advanced applications.
Area of Science:
- Biomaterials science
- Chemical engineering
- Molecular biology
Background:
- Coacervate droplets are versatile for encapsulating biomolecules.
- Conventional methods for coacervate droplet formation often yield unstable droplets with broad size distributions.
- Developing controlled methods for coacervate droplet formation is crucial for their application in biomimetic systems.
Purpose of the Study:
- To investigate the formation of coacervate droplets using a microfluidic flow-focusing system.
- To compare the stability and size distribution of microfluidically formed droplets with those from conventional techniques.
- To demonstrate the potential of microfluidics for creating distinct, co-located populations of coacervate droplets for applications like cell-mimicking compartments.
Main Methods:
- Formation of coacervate droplets using poly(diallyldimethylammonium chloride) with adenosine triphosphate or carboxymethyl-dextran via microfluidic flow-focusing.
- Utilizing two parallel flow-focusing channels for simultaneous formation of distinct droplet populations.
- Assessing droplet stability and size distribution.
- Evaluating the coexistence and genetic material exchange between co-located droplet populations over time.
Main Results:
- Microfluidic flow-focusing produced coacervate droplets with improved stability and narrower size distributions compared to vortex dispersion.
- Two distinct populations of coacervate droplets containing different DNA oligonucleotides were simultaneously formed and co-located.
- These distinct populations remained in close proximity for up to 48 hours without detectable genetic material exchange.
- The microfluidic method demonstrated ease of scalability for droplet formation.
Conclusions:
- Microfluidic flow-focusing offers a robust and scalable method for generating stable coacervate droplets with controlled sizes.
- This technique facilitates the creation of spatially separated, cell-mimicking compartments capable of encapsulating different materials, including genetic information.
- The findings open avenues for advanced applications in synthetic biology, drug delivery, and diagnostics.
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