Biocompatible and pH-Responsive Colloidal Surfactants with Tunable Shape for Controlled Interfacial Curvature

Area of Science:

• Materials Science
• Colloid and Surface Chemistry

Background:

• Molecular-surfactant-stabilized emulsions often suffer from instability due to coalescence and Ostwald ripening.
• Amphiphilic particles offer stronger interfacial anchoring, leading to more stable Pickering emulsions.

Purpose of the Study:

• To develop a versatile method for fabricating biocompatible amphiphilic dimer particles.
• To create tunable particles that mimic nonionic molecular surfactants for emulsion stabilization.

Main Methods:

• Controlled coprecipitation and phase separation were used to synthesize dimer particles.
• The dimer particles feature a hydrophobic polylactic acid (PLA) bulb and a hydrophilic shellac-polyethylene glycol (PEG) bulb.
• Particle size and diameter ratio were tuned to control interfacial curvature.

Main Results:

• The fabricated dimer particles effectively stabilized emulsions against coalescence and Ostwald ripening.
• Emulsion stability was maintained over extended periods.
• A pH-triggered response was demonstrated for emulsion destabilization.

Conclusions:

• Biocompatible amphiphilic dimer particles offer a robust alternative to molecular surfactants for creating stable Pickering emulsions.
• Tunable particle morphology and functionality enable precise control over emulsion properties.
• These particles show significant potential as colloidal surfactants in diverse applications.