Tuning Properties of Polyelectrolyte-Surfactant Associates in Two-Phase Microfluidic Flows

Area of Science:

• Materials Science
• Chemical Engineering
• Biomedical Engineering

Background:

• Polyelectrolyte-surfactant complexes (PSCs) are crucial for drug delivery.
• Traditional bulk synthesis methods lack precise control over PSC properties.
• Microfluidic confinement offers a promising alternative for controlled synthesis.

Purpose of the Study:

• To identify and prioritize factors controlling PSC properties in microfluidic confinement.
• To compare microfluidic synthesis with macroscopic methods.
• To explore the potential of microfluidic PSCs in drug delivery systems.

Main Methods:

• Characterization of polymer and surfactant flow conditions in two-phase microfluidics.
• Experimental and numerical analysis of supramolecular reactions in microscale droplets and threads.
• Quantitative analysis of capillary numbers and flow rate ratios.
• Development of a combined thread-droplet synthesis mode.

Main Results:

• Microfluidic confinement allows quantitative control over PSC properties by adjusting flow conditions.
• The thread-droplet mode produces PSCs in a broader size range (70-200 nm) compared to bulk methods (100-120 nm).
• Microfluidic synthesis yields PSCs with lower dispersity (PDI = 0.2-0.25) than bulk methods (PDI = 0.3-0.4).

Conclusions:

• Two-phase microfluidic confinement provides superior control over PSC formation compared to macroscopic conditions.
• The developed microfluidic approach enables tailored synthesis of PSCs for biomedical applications, particularly drug delivery.
• This method minimizes post-chip reactions and enhances aggregate uniformity.