Droplet breakup pack
Controlled and spontaneous droplet splitting in a microfluidic chip
Passive droplet breakup
No complex active splitting geometries
Ideal for artificial life models
Hosts functional molecular complexes at the water-oil interface
Tunable breakup timing
Controlled by flow rate and surfactant concentrations
Intrinsic chemical mechanism
Driven by non-equilibrium surfactant dynamics
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The representative animation of droplet division in a microfluidic channel was generated using Gemini’s Nano Banana Pro.
Microfluidic Spontaneous Droplet breakup
Achieving droplet splitting in microfluidics has historically required complex channel geometries, such as T-junctions with obstacles, or external active forces. Now, you can achieve spontaneous splitting of water-in-oil emulsion droplets using the Droplet breakup Pack!
Based on the principle of non-equilibrium catanionic surfactant systems [1], this all-in-one solution allows researchers to generate droplets that spontaneously divide into two or more daughter droplets after a specific lag time.
Unlike the static oil-in-water experiments described in early literature [2,3], this pack is optimized for water-in-oil (W/O) emulsions in a continuous flow microfluidic chip. By injecting an anionic surfactant solution downstream of the droplet generation, the system triggers a transient instability [1] that pulls the droplet apart.
A standard droplet breakup pack contains two pumping channels to push the two fluids to generate water-in-oil droplets in a microfluidic chip. It also includes an additional pressure channel for injecting a surfactant solution downstream. Flow rates can be measured and precisely controlled, thanks to high-precision Galileo flow rate sensors.
Droplet splitting setup
A preassembled pack guarantees compatibility between the chemical reagents and the microfluidic hardware. It is piloted by our flexible software, which precisely controls the flow rates, thereby controlling the timing of the division event.
The Droplet breakup pack contains:
High precision pressure pump
3x Galileo flow sensor
Software (Galileo user interface for flow stability)
Droplet splitting Chip (Flow-focusing junction with downstream injection port)
Chemical Starter Kit
The chemical starter kit can be:
- Cationic surfactant (e.g., CTAB) for the dispersed aqueous phase
- Anionic surfactant (e.g., Fatty acid/Oleate) for the trigger solution
All necessary accessories: Tubing, connectors, filters
Spontaneous Droplet splitting Principle
The spontaneous splitting utilized in this pack is driven by a transient decrease in interfacial tension in a catanionic surfactant system.
- Droplet Generation: Aqueous droplets containing a cationic surfactant are generated in an oil phase using a standard flow-focusing junction.
- Trigger Injection: Downstream, a solution containing an anionic surfactant is introduced into the channel.
- Non-Equilibrium Instability: As the anionic surfactant diffuses to the droplet interface, it pairs with the cationic surfactant. This momentarily lowers the interfacial tension to near-zero values.
- Shape Change & breakup: The droplet destabilizes, elongating into a toroidal or dumbbell shape due to internal Marangoni flows, and eventually breaks into smaller daughter droplets.
- Stabilization: As the system approaches equilibrium, the interfacial tension rises again, stabilizing the newly formed daughter droplets.
This process mimics rudimentary cell division, making it a powerful tool for bottom-up synthetic biology and “artificial life” research [4].
Customize your pack
The Droplet splitting chip and chemical kits are fully customizable to suit your specific “artificial life” [2] or emulsion splitting experiments.
For Water-in-Oil (W/O) droplets, surface properties are critical to prevent wetting.
- Hydrophobic Glass: Standard for robust chemical resistance, especially when using organic solvents like nitrobenzene.
- Fluorophilic Polymer: Recommended if using fluorinated oils for high-stability biological encapsulation.
- Channel Dimensions: Select nozzle sizes from 10 µm to 100 µm to define your initial parent droplet volume.
Surfactant starter kits:
The number of daughter droplets generated per breakup event depends strictly on the surfactant pair and concentration ratios used [1]. We offer pre-optimized catanionic pairs:
- Binary Fission Kit (CTAB / Decanoate): Optimized to split one parent droplet into two equal daughter droplets.
- Multiple Fission Kit (CTAB / Oleate): Generates three or more daughter droplets on average.
- Burst Fission Kit (DTAB / Oleate): Creates a “burst” of ten or more micro-droplets for massive parallelization.
Reaction Control Modules:
- Delay Lines: We can integrate serpentine channels of varying lengths to precisely tune the “lag time” (typically 5–10 seconds) between droplet generation and the spontaneous breakup event.
- Downstream Injection: Add a second injection port to introduce the trigger surfactant after droplet formation, ensuring splitting occurs exactly where you want it in the channel.
You can contact our researchers to answer any questions about this droplet breakup pack and how it can match your specifications.
Frequently asked questions
Can I control the number of daughter droplets?
Yes. Research shows that specific surfactant pairs dictate the breakup behavior. For example, pairing CTAB (in the aqueous phase) with Decanoate (in the oil phase) typically yields two daughter droplets, whereas using DTAB yields over ten [1]. Our experts can help you select the right pair for your desired output.
Will the droplets fuse back together after splitting?
No. Once the breakup event is complete, the system approaches equilibrium and the interfacial tension rises again, stabilizing the daughter droplets [1]. They remain separate and stable, making them suitable for further downstream analysis or collection.
Why use this instead of a standard droplet splitter?
Standard splitters require precise alignment and high flow rates to mechanically break droplets. Spontaneous fission is “intrinsic”—it happens automatically due to the chemical composition. This is particularly useful for modeling biological cell division, studying non-equilibrium thermodynamics, or creating self-replicating chemical systems.
Is this compatible with biological samples?
While the original research utilized nitrobenzene (an organic oil) [1], our pack can be adapted for biocompatible oils. However, please note that the “breakup” mechanism relies on specific ionic surfactant interactions, so compatibility with sensitive enzymes or cells should be tested.
Can a pack be customized based on my specific application?
Yes! Our experts will establish which instruments are best suited for your application, such as the type of flow sensor or the number of flow controller channels you need to perform your experiment. Drop us a line at innovation@microfluidic.fr.
Reference
- Caschera, Filippo, Steen Rasmussen, and Martin M. Hanczyc. “An oil droplet division-fusion cycle.” ChemPlusChem 78.1 (2013): 52.
- Sumino, Yutaka, et al. “Spontaneous deformation of an oil droplet induced by the cooperative transport of cationic and anionic surfactants through the interface.” The Journal of Physical Chemistry B 113.48 (2009): 15709-15714.
- Okada, Masahide, et al. “Spontaneous deformation and fission of oil droplets on an aqueous surfactant solution.” Phys. Rev. E (2020).
- Zwicker, David, et al. “Growth and division of active droplets provides a model for protocells.” Nature Physics 13.4 (2017): 408-413.
