Microencapsulation of Organic Solvents in Polyelectrolyte Multilayer Micrometer-Sized Shells

Area of Science:

• Materials Science
• Colloid Science
• Nanotechnology

Background:

• Fabrication of hollow-shell particles is crucial for encapsulation and controlled release applications.
• Existing methods often require complex procedures or harsh chemicals.

Purpose of the Study:

• To develop a facile method for creating stable, hollow-shell micrometer-sized particles.
• To demonstrate the ability of these shells to disperse in various organic and aqueous media.
• To show the encapsulation capabilities of these shells.

Main Methods:

• Stepwise deposition of oppositely charged polyelectrolytes onto sacrificial cores (melamine latex or cells).
• Dissolution of the core to yield hollow shells.
• Gradual solvent exchange for suspension in organic media.
• Transfer to aqueous media to form oil-in-water suspensions.
• Phospholipid adsorption for organic solvent-in-water dispersions.

Main Results:

• Successfully fabricated hollow-shell micrometer-sized particles in aqueous media.
• Demonstrated suspension of shells in diverse organic solvents (alcohols, alkanes).
• Achieved stable oil-in-water suspensions without surfactants.
• Confirmed shell integrity across different solvents using AFM.
• Showcased solvent encapsulation and phospholipid adsorption via confocal microscopy.

Conclusions:

• The developed method provides a versatile route to hollow-shell particles.
• These particles exhibit excellent stability and dispersibility in various media.
• The shells can effectively encapsulate solvents, opening possibilities for advanced material design.