Related Experiment Video
Updated: Jun 15, 2026
11:08
Generation of Size-controlled Poly ethylene Glycol Diacrylate Droplets via Semi-3-Dimensional Flow Focusing Microfluidic Devices
Published on: July 3, 2018
7.8K
Squeezing Droplet Formation in a Flow-Focusing Micro Cross-Junction
Filippo Azzini1, Beatrice Pulvirenti1, Massimiliano Rossi1
1Department of Industrial Engineering, Alma Mater Studiorum Università di Bologna, Viale Risorgimento 2, 40136 Bologna, Italy.
Micromachines
|March 28, 2024
Summary
This study presents a new model for droplet creation in microfluidic devices, crucial for medical applications. It offers a novel correlation to optimize the design of micro-drop generators.
Area of Science:
- Microfluidics
- Fluid Dynamics
- Biomedical Engineering
Background:
- Growing demand for optimized micro-devices in medical and biological applications.
- Flow-focusing micro cross-junctions are key for droplet production.
- Channel cross-section restrictions enhance flow focusing for droplet formation.
Purpose of the Study:
- To develop an integrated approach for studying liquid-liquid droplet creation in flow-focusing micro cross-junctions.
- To analyze forces acting on the dispersed phase during droplet formation.
- To develop a droplet breakup model under the squeezing regime.
Main Methods:
- Numerical simulations using OpenFOAM.
- Validation through experimental results from high-speed camera images.
- Micro-particle Image Velocimetry (micro-PIV) measurements.
Main Results:
- Analysis of forces and droplet diameter during numerical simulations.
- Development of a droplet breakup model based on energy balancing.
- A novel correlation between dimensionless droplet length and dimensionless flow rate.
Conclusions:
- The study provides a new model for droplet breakup in micro-junctions with restrictions.
- A novel correlation aids in optimizing micro-drop generator design.
- Expands knowledge on droplet creation phenomena in microfluidic devices.
Related Concept Videos
01:26Cross-bridge Cycle
As muscle contracts, the overlap between the thin and thick filaments increases, decreasing the length of the sarcomere—the contractile unit of the muscle—using energy in the form of ATP. At the molecular level, this is a cyclic, multistep process that involves binding and hydrolysis of ATP, and movement of actin by myosin.
01:16Cell Motility through Blebbing
Blebs are a type of membrane protrusion formed by the internal hydrostatic pressure of the cytoplasm. Blebs are observed in several cell types, including fibroblasts, immune cells, and single-celled organisms like the amoeba. The primary function of blebs is cell locomotion and apoptosis, but they are also found during necrosis and cell division. The life cycle of a bleb comprises an initiation phase followed by the expansion and retraction phases.
Blebbing Through the Matrix
In multicellular...
Blebbing Through the Matrix
In multicellular...
01:39Mechanism of Filopodia Formation
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
01:31Mechanism of Lamellipodia Formation
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
01:32Pinching-off of Coated Vesicles
Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...