Modulation of Oil/Polymer Nanocapsule Size via Phase Diagram-Guided Microfluidic Coprecipitation

Area of Science:

• Materials Science
• Chemical Engineering
• Fluid Dynamics

Background:

• Flow-based nanoprecipitation is a scalable method for nanoparticle manufacturing.
• Controlling nanoparticle size in this process often relies on empirical adjustments.
• The Ouzo effect offers a route to forming nanocapsules via liquid-liquid mixing.

Purpose of the Study:

• To establish a systematic approach for controlling nanocapsule size in flow-based nanoprecipitation.
• To link in situ precipitation conditions to ternary phase diagram behavior.
• To investigate the role of supersaturation in nanocapsule formation and size.

Main Methods:

• Utilized glass capillary microfluidics for coprecipitation of oil and polymer.
• Employed computational fluid dynamics (CFD) simulations.
• Correlated experimental precipitation conditions with the ternary Ouzo phase diagram.

Main Results:

• Identified the degree of supersaturation in the vortex zone as a key variable for nanocapsule size.
• Demonstrated a strong correlation between supersaturation of oil and polymer and resulting capsule diameter.
• Showcased size control by varying supersaturation using oils with distinct phase diagrams.

Conclusions:

• Developed a systematic method to control nanoparticle size in continuous nanoprecipitation.
• Linked microfluidic flow conditions to ternary phase diagram behavior for precise size control.
• Established supersaturation as a critical parameter for tuning nanocapsule dimensions.